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longwolf
05-16-2010, 01:24 AM
I was considering using silicone to seal cells directly to the glass, when I ran across one of Mikes posts where he warns to only use electronics grade silicone.
Pricing the stuff, you may as well go with Slyguard.

But then I spotted this from Liquid Nails:
http://www.liquidnails.com/products/product.jsp?productId=5

What do y'all think, could it work?

Mike90250
05-16-2010, 01:39 PM
Maybe, depends on the product's shrinkage as it cures.

Clear Seal All Purpose Sealant (CS-145)

From their PDF, it's 58% solids, and 47% shrinkage as it cures. Id try it on a single cell, and see what the shrinkage does.

longwolf
05-18-2010, 10:04 PM
Thx Mike,

I may have found a better one on their site.
It's a silicone with an Acetoxy cure.

LIQUID NAILS

phillam
06-11-2010, 08:51 AM
Longwolf,

from what I have read vapour tansfer (ie water entry) is the major issue in encapsulation. I am not sure of the specific vapour permeability of the silicon you reference but there is some research on specific silicon products that show silicon to be a poor membrane and when you are talking about a large surface area it might be an issue. I suppose it depends on the life you are after of your cells. Short term shouldn't be a problem but long term it could reduce your output considerably.

I looked at a similar concept using flexible water membranes such as those used in pond linings and bathroom sealers but I was concerned about the premeability so I am testing something else at the moment using commercial grade al-foil and vacuum adhering. (all DIY stuff).

I would be interested in how you go with the pouring if you try it.

Good luck!

longwolf
06-11-2010, 09:25 AM
Longwolf,

... so I am testing something else at the moment using commercial grade al-foil and vacuum adhering. (all DIY stuff).....

I'm not committed to silicone, just tying to find something I can afford :)
What do you think your method will cost you per panel?

muskrat
06-11-2010, 05:29 PM
regular household silicone rubber produces acetic acid when it cures.This will swiftly corrode electrical connections.This is why it is never used for sealing electrical connections.

longwolf
06-12-2010, 12:20 AM
regular household silicone rubber produces acetic acid when it cures.This will swiftly corrode electrical connections.This is why it is never used for sealing electrical connections.

Mike mentioned that a vinegar smell meant you'd do damage.
I believe he said an acetone base silicone was safe.

LiquidNails says that their LS-205 uses a Acetoxy cure.
I was hoping that was some type of acetone cure.
Are you saying Acetoxy produces acetic acid?

Maybe I'll have to try their CS-145 instead.

phillam
06-12-2010, 09:41 AM
I think everyone would love that miracle cheap product (well except companies like DuPont that is). Seems to me if the method is cheap you are always sacrificing in one area.

That probably applies to what I am attempting...especially when I am going for around $15 per panel (encapsulation). The traditional techniques put DIY panels out of my range so I am trying to think out of the box. I also have a budget limit based on govt rebates I am working within to make a cost netural system.

Al-Foil ( or really thin al sheeting) has some great properites: reflectivity, heat dissipation, malleability, (almost) no vapour permeability and cheap! There are obviously bad properties as well but I am working on these.

At the moment I am focussing on the big killers; moisture ingress, heat dissipation, varying thermal expansion and price. Anyway I'm planning a range of tests in the coming weeks so I will let you know how I go with the process.

Whilst I am here does anyone know of a 2 part adhesive with good UV/heat tolerant properties? Epoxy was my first thought but I am not happy with it's poor UV stability especially when we are talking solar panels. I am not intending to encapsulate just using as a light adhesive within the panel. Polyurethanes look better for UV but I am not sure of heat and adhesion.


I'm not committed to silicone, just tying to find something I can afford :)
What do you think your method will cost you per panel?

longwolf
06-29-2010, 01:35 PM
Id try it on a single cell, and see what the shrinkage does.

Great idea!
Instead of wasting a cell, I got some cheap picture frames from a dollar store.
One 8.5x11 as the glass and two 4x6's to use as simulated solar cells.
I cut one of the 4x6's in two so I would also have a T intersection/joint.

I used the Clear Seal which is a synthetic rubber.
My first attempt failed because I only gave it 12 hours to dry. The spec sheet says 5 days to a full cure.

But the second try is working well. I placed some black paper under the glass and put the whole thing in between my windshield and a reflective sun screen.
After several hours of pointing at the Texas summer sun, they were too hot to touch.
But I still tried to gently push the 'cells' around on the glass. They held firm! :)

I plan to try soaking them in water then freezing and reheating them several times as a full test.

There was shrinkage, but it just got thinner without pulling away from the edges of the glass.

This stuff is very clear. If I can thin it enough, I think it could be used like slyguard.

Question, I need a thinner that won't hurt the cells. The Clear Seal says to clean up with mineral spirits but I think acetone or denatured alcohol might work as well.
Would any of those be safe?

I have a light meter so I'll be able to measure how much difference having the Clear Seal between the plates will make.

muskrat
06-29-2010, 03:19 PM
Regular home silicone rubber will work for a few months before the acetic acid causes corrosion.It will do a good job of sealing the cells from water but the problems come later.Perhaps you could put some fine copper wire on a glass plate and cover it with this clear seal stuff and then wait several months to see if the copper corrodes? I was thinking of using polyester resin which is very sunlight resistant but that would only work on the back of the cells since anything on the front would not dry.I was also considering a very high melting point wax but I doubt it would be clear enough for the front of the cell.The wire from a old set of headphones is very thin and might show any corrosion quickly.

longwolf
06-29-2010, 05:31 PM
...Perhaps you could put some fine copper wire on a glass plate and cover it with this clear seal stuff and then wait several months to see if the copper corrodes?.....

Well, I don't have months to wait.
I'm living out of my van and need the power months ago.
Also, I'd rather not have the cells bouncing around in their box any longer than they have to :)

I don't believe the Clear Seal is a silicone based rubber.
The tube lists a number of benzene compounds.
It also says, "Stays crystal clear, Will not yellow, Weatherproof, indoor/outdoor use and 50 year durability"

Mike says the electronics grade silicone uses an acetone cure, I believe I've read that slyguard is an alcohol cure.

I'm just looking for advise on the safest solvent for thinning.

longwolf
07-04-2010, 12:36 AM
Here's an update.
I've done some testing where I only used the CS (Clear Seal) to seal the edges of my test 'cells'.
I've heated them under my windshield, soaked them in water, frozen them and heated them again.
And there's no sign of vapor between the pains of glass!

Today I began tests on thinning the CS.

First I tried acetone. It thinned it, but then it turned milky.
Next it reacted with the CS and kind of turned it into a foam.
One thinner down.

Next I tried denatured alcohol.
Again, it turned the CS white.
But it wouldn't thin or even mix with the CS.

Finally I tried mineral spirits.
It worked great!
You do have to be careful not to whip in bubbles.
I poured some on a piece of glass and placed a smaller piece on it. It looks about like water between the pains. If/when it drys, I'll test it with a light meter.

Mike90250
07-04-2010, 12:03 PM
Finally I tried mineral spirits.
I worked great!
You do have to be careful not to whip in bubbles.

A simple vacuum bag can get rid of the bubbles, and make a tighter sandwich, if it's all flat, nothing will crack, but if tab wire is thick, and lumps of solder, that will shatter cells as the vacuum flattens everything out. Or wip up your thinned mix, vacuum the air bubbles out, and then pour.

longwolf
07-04-2010, 01:07 PM
A simple vacuum bag can get rid of the bubbles, and make a tighter sandwich, if it's all flat, nothing will crack, but if tab wire is thick, and lumps of solder, that will shatter cells as the vacuum flattens everything out. Or wip up your thinned mix, vacuum the air bubbles out, and then pour.

I've been thinking of that. I haven't done any tabbing yet, so we'll have to see.

When the CS is thinned 50/50 with the mineral spirits it's pretty thin and the bubbles rise quickly. So another idea would be to take a funnel, cap the end, pour in the thinned mixture, let the bubbles rise then pour off the bottom off the funnel.

longwolf
07-05-2010, 12:11 PM
Another update.
The thinned CS around the simulated cells has dried to the touch.
I believe it's still liquid between the pains, but it may take a couple of weeks for a full cure.

I didn't want to wait for the light test.
And I had a very surprising result!

I cleaned the glass on on the test pieces.
Each piece is about one millimeter thick, so the tests pass through a total of 2 millimeters of glass.

I setup the light meter in a bathroom. It read 444 lux, without any glass in front of it.

I tested the sample that only had CS around the edges, it read 353 lux.

Next I tested the the one with CS between the pains. It read 385 lux!

I did the test a couple of times to make sure, but the tests that read through the CS where always higher!

My best guess is that the CS caused the two pains to act like a single piece of glass and reduced the losses caused by refraction.

Anyway, I'd call that a very successful test and it gives another good reason for encapsulation.

crxvfr
07-06-2010, 03:50 PM
Last summer I got curious about making dash and motorcycle tank covers from silicone rubber. I bought several caulking tubes of silicone and thinned it with naptha until it would go thru my paint sprayer. It worked pretty well but I had to do things in layers. Spray, wait, spray, wait. The naptha seemed to completely evaporate leaving the silicone the same consistency/texture when cured as if it had come out of the caulking tube, and the mixture was obviously thin enough to pour and level itself.

Edit Add: Maybe you could put a thin film of the expensive silicone down (or some kind of sprayable insulating coating), then more coats of regular silicone, ...last coat maybe topped of with a laminate made for counters or cabinets.

Sounds like you have the CS working. ...just contributing ideas.

crxvfr
07-06-2010, 06:58 PM
Scotch 1602 Insulating Spray (http://products3.3m.com/catalog/us/en001/government/innovative_solutions/node_GSM1HQS0PWgs/root_GS3RBW6QFVgv/vroot_31S2JJ7584ge/bgel_GSNC8RDPS7bl/gvel_H5BG3FHVD4gl/theme_us_innovativesolutions_3_0/command_AbcPageHandler/output_hTml)
$30.00

How about this stuff? Might it protect connections from the acids in silicone?

longwolf
07-06-2010, 07:22 PM
Scotch 1602 Insulating Spray (http://products3.3m.com/catalog/us/en001/government/innovative_solutions/node_GSM1HQS0PWgs/root_GS3RBW6QFVgv/vroot_31S2JJ7584ge/bgel_GSNC8RDPS7bl/gvel_H5BG3FHVD4gl/theme_us_innovativesolutions_3_0/command_AbcPageHandler/output_hTml)
$30.00

How about this stuff? Might it protect connections from the acids in silicone?
Not to shoot you down, but it's opaque so you could only use it on the backs of the cells, and you'd have to be very careful to keep it off the fronts.
It would totally rule out complete encapsulation.
And by the time you payed for the spray and the silicone, you may as well spend $10 more and go with slyguard :(

crxvfr
07-06-2010, 07:51 PM
Not to shoot you down, ....(

Ha, don't worry about that. If I was gonna let myself get shot down, it would have happened a long time ago. They keep telling me no, or I can't, and I keep asking questions.

Sorry. Only part of my head has been here.
I've been reading other DIY threads and forgot you want to encapsulate it completely.
There has to be stuff that will work but not cost TOOOOO much money.

I used to work with fiberglass. The resin we used was different but, it's all the same. Casting resin comes to mind. I'm not all scientific and all, but maybe they make optical grade casting resin (http://www.globalspec.com/datasheets/4043/areaspec/type_optical_grade)? Learn what you are working with and you can add stuff to make it stiffer, slower curing, etc. Here is a place I like to browse.

Thomas Registry (http://www.thomasnet.com/).

It sounds like you are doing things properly and know what you are doing, but skimping a little :eek: (not to shoot you down :) )

I don't know what you are after but it sounds like your smart enough to get it done.

BTW, one of the drawbacks of casting resin is the same as plexiglass, and I would imagine the same as CS. Long exposure to UV and you'll end up with that cloudy look you got with acetone. I am not sure about the optical grade stuff. Seems like it would be less to reactive to UV than the others. dunno.

Good luck. I just bought 1kw of the same cells.

longwolf
07-07-2010, 12:19 AM
It sounds like you are doing things properly and know what you are doing,
Haven't got a clue, that's why I'm asking so many Q's and doing tests.


but skimping a little :eek: (not to shoot you down :) )
Well, if I can save $100 per panel on the three panels, that's $300.
I had a period last year when that was about all I made in four months.


BTW, one of the drawbacks of casting resin is the same as plexiglass, and I would imagine the same as CS. Long exposure to UV and you'll end up with that cloudy look you got with acetone.
This stuff claims to be be for outdoor use, stays clear and will last 50 years.
Here's hoping they're not lieing :)


Good luck. I just bought 1kw of the same cells.
Let me guess, fredv480?
Good luck with your panels too!

longwolf
07-07-2010, 12:28 AM
A little set back.
I went to Home depot to get them to order the 10 oz tubes of Clear Seal.
Turns out they discontinued it, you can only get it in the 5.5 oz tubes.
I was hoping the large tubes would be cheaper, but you can still get the 5.5's at Walmart for $3.97 a tube.

But $0.72 per oz is still better than what, $2.50 per oz for slyguard?

I just wonder how many chinamarts I'll have to raid per panel :)

crxvfr
07-07-2010, 02:14 PM
Let me guess, fredv480?
No, but I talked to him too.
He seems like a righteous dude, so to speak.
I may buy from him next time.

I got a $50 discount from somebody else because I had pointed out an error in their listing. 1kw for 392.00 shipped.

BTW, I was trying to find the CS you speak of.

By Liquid Nails (http://www.liquidnails.com/products/product.jsp?productId=4#details)? You should just about be able to but that (this) stuff by the 5 gallon bucket.
* Excellent adhesion
* Paintable
* Permanently flexible
* Stays crystal clear
* Weatherproof seal
* Will not yellow

There is a datasheet on that page too.

longwolf
07-07-2010, 06:08 PM
That's the stuff.
But we were told they only sell the small tubes now.
You should be able to find it in the paint dept's of most walmarts.

crxvfr
07-07-2010, 07:56 PM
bummer. I looked around and did not see it.

I found out the insulating varnish comes in clear. By Krylon no less.

cby016
07-26-2010, 06:58 PM
Longwolf have you built a solar panel using clear seal to encapsulate it yet? If so how did it turn out. I haven't looked for it in stores but online the 10 oz tube is still available.

http://www.google.com/products?hl=en&q=liquid%20nails%20clear%20seal&um=1&ie=UTF-8&sa=N&tab=wf

longwolf
07-26-2010, 07:07 PM
Longwolf have you built a solar panel using clear seal to encapsulate it yet? If so how did it turn out. I haven't looked for it in stores but online the 10 oz tube is still available.

http://www.google.com/products?hl=en&q=liquid%20nails%20clear%20seal&um=1&ie=UTF-8&sa=N&tab=wf

Not yet, I've only been able to work on this on weekends, and only when I have the money for the next set of materials.

And, Great find!
But I do wonder how old it is, I think I read that it's only got a couple of years worth of shelf life.

DrRobot
07-26-2010, 08:43 PM
Longwolf have you built a solar panel using clear seal to encapsulate it yet? If so how did it turn out. I haven't looked for it in stores but online the 10 oz tube is still available.

http://www.google.com/products?hl=en&q=liquid%20nails%20clear%20seal&um=1&ie=UTF-8&sa=N&tab=wf
I've been testing with DAP Clear on some of my cells and polycarbonate plexi. It's working pretty good. To get it as fluid as Sylgard you have to quite a bit of Mineral Spirits. Also, the DAP Clear turns a little cloudy, but when you pour it out it's not bad. Soon, I'm going to mix up a bucket of Liquid Nails Clear Seal and Mineral Spirits.

One of the other things that I've come across in my tests is that after mixing the beads of DAP Clear and Mineral spirits you need to let it sit to complete dissolve and let it thin. Also after letting it sit, you can stir it again or you can swirl to get the stuff that settled on the bottom mixed together.

One more thing, if you're like me and set the cell on your glass/plexi first, make sure you don't go around all the edges of each cell. When you do that you seal the air in below it, so go around 3 sides of the cell and let it sit to avoid sealing air in. I'm going to do a few more tests on single broken cells to get things figured out.

longwolf
07-26-2010, 09:45 PM
I've been testing with DAP Clear on some of my cells and polycarbonate plexi. It's working pretty good...... .

Cool, so the mineral spirits isn't harming the plexi?

Hopefully your material will clear up as it drys.
I didn't see any clouding with the CS.

With luck, I'll be doing my pour this coming weekend.

DrRobot
07-26-2010, 10:01 PM
The plexi is perfect.

The mixture clears up, I've already tested the mixture on some other busted cells.

Good luck!

longwolf
07-26-2010, 10:18 PM
DrRobot,

Just checked the tech sheet on your DAP.
http://www.dap.com/docs/tech/00077019t.pdf
Sounds a lot like the CS, but with a better heat range.
Be sure to use a good respiratory, these materials have some pretty nasty stuff in them.

Oh, and be careful, DAP also has a clear silicone and I'll bet it's the type that would eat your cells.

cby016
07-27-2010, 10:47 AM
The dap sounds like a good alternative. I was searching around last night and found some other possible alternatives.

Sashco (Sealants) 14010 "Through The Roof" Elastomeric Roof Sealant 10.1 Oz. - Clear
http://www.acehardwareoutlet.com/productdetails.aspx?sku=1204445&source=GoogleBase

Sashco (Sealants) 14004 "Through The Roof" Roof Sealant 1Gal.
http://www.acehardwareoutlet.com/productdetails.aspx?sku=1204460&source=GoogleBase

CRL Clear Dow Corning Silicone Glazing Sealant
http://www.dkhardware.com/product-17911-dc1c-clear-dow-corning-silicone-glazing-sealant.html

Elastomeric Epoxies
http://www.epoxy.com/elastomeric.aspx

longwolf
07-27-2010, 11:12 PM
The dap sounds like a good alternative. I was searching around last night and found some other possible alternatives.
.......

Thx cby016,
You need to check them carefully and make sure they don't let off acetic acid which damages cells.

DrRobot
07-29-2010, 06:14 PM
The dap sounds like a good alternative. I was searching around last night and found some other possible alternatives.

Sashco (Sealants) 14010 "Through The Roof" Elastomeric Roof Sealant 10.1 Oz. - Clear
http://www.acehardwareoutlet.com/productdetails.aspx?sku=1204445&source=GoogleBase

Sashco (Sealants) 14004 "Through The Roof" Roof Sealant 1Gal.
http://www.acehardwareoutlet.com/productdetails.aspx?sku=1204460&source=GoogleBase

CRL Clear Dow Corning Silicone Glazing Sealant
http://www.dkhardware.com/product-17911-dc1c-clear-dow-corning-silicone-glazing-sealant.html

Elastomeric Epoxies
http://www.epoxy.com/elastomeric.aspx
The gallon of the brushable sashco sealant doesn't look bad, maybe I'll try that on my next panel.

smoothbrad
08-06-2010, 03:51 PM
A 2-part platinum-based (Addition cure) room temperature vulcanizing (rtv) silicone rubber is most suited because during the cure cycle this material will not exude any by-products such as acetic acid and alcohol, both of which are associated with tin-based silicones.

Platinum based systems do not need to be thinned out with any solvents either, and are considered to be archival in the sense that they will not modify or change over time. Solaris

longwolf
08-06-2010, 10:29 PM
[QUOTE=smoothbrad;11737]A 2-part platinum-based (Addition cure) room temperature vulcanizing (rtv) silicone rubber is most suited because during the cure cycle this material will not exude any by-products such as acetic acid and alcohol, both of which are associated with tin-based silicones.

Platinum based systems do not need to be thinned out with any solvents either, and are considered to be archival in the sense that they will not modify or change over time. Solaris

smoothbrad
08-06-2010, 11:34 PM
You are correct.
I come as a friendly contributor; I am willing to offer my 13 years of industrial silicone experience to this industry.
But if my presence aggravates you or anyone, then I will stay away from the forum.
Honestly, I posted this to see if anyone would respond.
So I must apologize, but I do not know the exact price right at this moment as I am at home on Friday night 11;30 pm. We do have pricing though and it will be on our site shortly.
Off the top of my head, I can tell you it is VERY competitively priced - less than the DC material for sure.
I will post the price soon this coming week... if ok.
In the meantime,
Would you like to try some?

longwolf
08-07-2010, 09:50 AM
.... if my presence aggravates you or anyone, then I will stay away from the forum. .....

I can't speak for the forum moderators, but as long as you have a viable product at a good price and your not just spamming the forum, I'm happy to hear from you.



I will post the price soon this coming week... if ok.

Great!



In the meantime,
Would you like to try some?
Sure, I'd even do a test on it with my light meter.

Mike90250
08-07-2010, 12:38 PM
But if my presence aggravates you or anyone, then I will stay away from the forum.

Contributers are welcome.. we just don't always get to it right away. Welcome

DrRobot
08-08-2010, 02:30 PM
So. I got that liquid nails clear seal all mixed together with the mineral spirits. I used a whole tube of liquid nails and and a pint of mineral spirits, half of this:
http://www.homedepot.com/h_d1/N-5yc1vZ1xj3/R-100251041/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

I put the mineral spirits in first, then I mixed in the whole tube of clear seal. I stirred it up, and then let it sit all night. The next morning some of the clear seal had settled, so I stirred it again, It resulted in a pretty good mixture, flowed probably as good as sylgard.

I poured the mixture kind of like that guy markp on youtube, like this:
http://www.youtube.com/watch?v=Muwclw5oYd8

I had the same layout, 4x9, But I went around the outside of the panel, then went down the middle, and then went across each row. Waited, A lot of the bubbles removed them selves because I only went around 3 sides of each cell. Then after most of the air was gone from below the cells, I went down the 2 remaining gaps. Sat some more for most of the mixture to get below the cells then I fished out the bubbles. With the little bit of remaining mix, I poured it over the backs of the cells.

It's been sitting for about 2 days, it's still a little wet below the cells. They weren't lying on the tube of liquid nails, It does a little while for it to dry. But, it probably doesn't help that the panel is in my basement. It's not exactly warm or sunny down there.

Mike90250
08-08-2010, 06:19 PM
slow dry is likely better, less stress develops

Minnesota
08-08-2010, 07:58 PM
Great thread. I have tried to make sense of making my own panels but the numbers just don't add up, and the slygard is a showstopper as it costs almost $1/watt.

I hope you guys come up with something brilliant and one that works on a plastic front, such as Lexan which is cheaper than safety glass.

One tip to get bubbles out of your mix jar is to use a vacuum sealer like they do for food, .... just takes seconds.
Such as: http://www.youtube.com/watch?v=R4Wk_0xVBbM
In use: http://www.youtube.com/watch?v=d4qdgQPTvn4

Here is a good vid on how they make panels commercially - using films rather than liquids:
http://www.youtube.com/watch?v=qYeynLy6pj8

Tom

Sizz
08-16-2010, 11:02 AM
You are correct.
I come as a friendly contributor; I am willing to offer my 13 years of industrial silicone experience to this industry.
But if my presence aggravates you or anyone, then I will stay away from the forum.
Honestly, I posted this to see if anyone would respond.
So I must apologize, but I do not know the exact price right at this moment as I am at home on Friday night 11;30 pm. We do have pricing though and it will be on our site shortly.
Off the top of my head, I can tell you it is VERY competitively priced - less than the DC material for sure.
I will post the price soon this coming week... if ok.
In the meantime,
Would you like to try some?

I'm very interested in the Solaris encapsulate from Smooth-On. A local distributer quoted me $78 for a 1qt kit which seems high considering Slygard is about $40 for a 0.5KG. I believe 1qt would be about two 0.5KG Slygard containers?

smoothbrad
08-18-2010, 04:27 PM
The Solaris in a quart kit has product that weighs 2.2 lbs / 1 kg - it works out to $ 35.38 / lb.

This material is a platinum-based addition curing silicone. In fact this type of formula contains a high amount of platinum, which enable the material to cure without outgassing, or giving off by-products the way acetoxy silicones cure.

So there is no deformation in the cured rubber over a long period of time; archival.

longwolf
08-18-2010, 11:35 PM
Thx Brad,
One concern, does being platinum based make it conductive?

smoothbrad
08-19-2010, 08:48 AM
no, platinum based silicones are non-conductive

longwolf
09-01-2010, 09:40 PM
Well, it's not my forum, just my thread :)

Yes, I have made one of my three panels and I did use the Clear Seal.
I tried something that didn't work well and I don't recommend it. I tried doing it in two pours and I only thinned the sealer at about 2/3's CS to 1/3 mineral spirits then laid the strings of cells on top of it. I ended up with quite a few bubbles to work out.
That's where I learned my second mistake, I forgot to wear a good respirator.
I was working outside under a covered porch, but that still wasn't enough fresh air.
By the time I'd gotten to the last few cells, I was so stoned and sick that I just didn't give a D@%^$ any more. So I still have bubbles.

After giving the panel a week to dry, I came back with a 50/50 mix of CS and mineral spirits which was poured over the backs of the cells. Despite the bubbles between the glass and a few cells, the panel seems well sealed.
You can see how the panel is preforming here:
http://www.solarpaneltalk.com/showthread.php?p=12081#post1208

It's been up a few weeks now and is doing great. Right now we're having the first real rain since the panel was mounted. I'll check it when things dry up, but I'm not worried about it.

You could consider the panel to be on a tracker now, it's on the top of my van :)
I'm still getting use to the idea of NOT parking under trees. Between the shade and the birds it's just a bad idea.
But the bonus is I can run all the fans I need all of the time!



Hi longwolf,
I`ve been following your forum and was wondering if you have had any success with clear seal?Also been looking at homemade trackers.I don`t know if it would do you any good but there`s alot of sites showing homemade trackers made from old printers.

longwolf
09-01-2010, 09:41 PM
errrrr, what happened to tlgoose's post that I was replying to?

tlgoose
09-02-2010, 06:07 AM
Sorry,New to this stuff and i deleted it by mistake.
Did the 50/50 work better or did you get more bubbles?
I`m wondering if a 50/50 mix and a little warmer mixture might make the bubbles rise out better.Or maybe some vibration with a warm mix.
After reading through all your threads and previous threads,i decided to go and get some cs and give it a wurl.Before i found your thread i made a panel.I had one screw on the top that snapped so like a fool i gave it a gentle tap with a hammer and snapped three cells in half but it really didn`t effect the voltage any,just looks poor.I`ll let you know if 50/50 warmed and vibed works after the weekend.One more thing,did you let it set for any time to bring bubles up or does it dry too fast for a day sit?
Another thing,i found that golf cart companys frequently change rented carts batteries and they are usually gel deep cycles and can usually get them real cheap.I happened to get 2 from a repairman for free with more then 50% life left in them.I also picked up a new one from craigslist from a guy(he had proof of purchase) for $35.Just an FYI.
Tlgoose

longwolf
09-02-2010, 07:04 PM
Yes, the 50/50 mix worked much better.
The small bubbles rise pretty well with it that thin.
I may even use a little more thinner next time.

I found a funnel at walmart that looks like a measuring cup with a funnel shaped bottom, they're in the automotive dept.. It also has a valve you can turn off, a hose, a plug for the hose and a lid for the top of the funnel.
I cut the hose off to about 2 inches and put the plug into it.
With the hose that short, you can pour in your pre-mixed sealer and stand the funnel up in a corner while the bubbles float up.
It worked very well.
I put the lid on the funnel after the first pour (there was still a little sealer in the funnel) and a week later that bit of sealer was still fluid so I was also able to use it for the second pour.

I did not try using heat or vibration, but it was over 100 degrees F out there.


I hope that helps and good luck with your panel(s).

nayubis
09-06-2010, 06:23 PM
Been following this thread & has gained a lot of insights before I start trying it myself. Thank you longwolf!

Question on your second test w/ the 50/50 mixture. When you poured the mixture over the backs of the cells, did the mixture seeped into or naturally flowed between the glass & the cells? Did you try to do something to remove the bubbles between the glass & the cells before the mixture dried?

Did you try the 2-pour method again?
Thanks. This is definitely a big help to all.

knowyourplanet
09-07-2010, 03:50 PM
Hi all,

QSIL 216 is a real alternative to Sylgard 184. It has the same properties and costs around almost half as little. (that was compared to UK seller, further research shows the prices are more or less the same, comparing best price US Sylgard 184 with Best price Europe Qsil 216, not including postage)

Prices are important as potting compound, while greatly extending the life of your DIY project, also constitutes up to a quarter of your total DIY costs.

You can find the product here:
http://www.knowyourplanet.com/shop/silicone-encapsulant

Happy building!

longwolf
09-07-2010, 07:45 PM
Part of why I tried doing it in two pours is because of the way the 6x6 cells are curved.
The idea was to get a layer of sealer down, lay the cells into it slowly, working out any large bubbles as I went. Then place weights on the backs of the cells to try to get them to flatten out close against the glass. But trying to slowly add 36 6x6 tabbed and bussed cells didn't work well. The thick mixture made it even worse and the weights were not enough to push the cells down into this mixture.

I tried working the bubbles out by gently pressing the backs of the cells. Again, the thick mixture was a problem. As it thickened more, and I became more stoned from the fumes, I started cracking cells and decided to leave well enough alone.

The second, thinner pour did fill a few of the voids, but for the most part the edges of the cells were already sealed.

I don't plan to try it with two pours again.
Next time I'll put the cells in place, clip down the busses on one side of the panel, make a dam (from un-cut sealer) around the other three sides of the glass, raise the un-dammed/buss side of the panel 1/4 to 1/2 inch and slowly pour thinned sealer into the low side of the panel. Once the sealer is covering 2/3 to 3/4 of the panel, I'll remove the clips, finish the dam, level the panel and complete the pour.

I'm still trying to figure a way to weight and flatten the cells against the glass.

Mike90250
09-07-2010, 09:00 PM
I'm still trying to figure a way to weight and flatten the cells against the glass.

Get a teflon vacuum bag (or whatever the bags are they use for surfboard lamination) and hook a small shop vac to it. It will squeeze and compress, and the bubbles will get sucked out. if things are not flat, it will conform the cells to the structure, and if they flex, they will crack.

longwolf
09-07-2010, 09:56 PM
Hi all,

QSIL 216 is a real alternative to Sylgard 184. It has the same properties and costs around almost half as little.

You can find the product here:
http://www.knowyourplanet.com/shop/silicone-encapsulant

Happy building!

Hi, just did the math.
It looks like the QSIL runs about $3 per oz. I think I figured Sylgard at $2.50 per oz.
Still, it's an alternative.

longwolf
09-07-2010, 10:33 PM
Get a teflon vacuum bag .......

Thanks Mike, but I don't think it will take the curve out.
Think of it this way, say the sealer is 1/16th of an inch thick and poured over the cells. When the air is removed from the bag, it's only going to compress down to that 1/16th. The cells inside the sealer would still be able to curve that amount.

knowyourplanet
09-08-2010, 05:01 AM
Hi, just did the math.
It looks like the QSIL runs about $3 per oz. I think I figured Sylgard at $2.50 per oz.
Still, it's an alternative.

The price of Sylgard 184 is (in the United states and without postage) now about 62 pounds for two kits of 500 g or 1 kg total
Qsil 216 is 65 pounds for 1.1 kg.

I guess they cost the same, my bad for getting the price comparison wrong :???:.

Sizz
09-08-2010, 01:19 PM
P-4 from Silicones, Inc. (http://www.silicones-inc.com/datasheets/pseries/p4.pdf)

It's a clear 2-part (10:1 ratio) platinum cure. It's very similar to sylgard (viscosity & cured hardness). 2lb kit costs $43.20. So about half the cost.

knowyourplanet
09-08-2010, 02:40 PM
P-4 from Silicones, Inc. (http://www.silicones-inc.com/datasheets/pseries/p4.pdf)

It's a clear 2-part (10:1 ratio) platinum cure. It's very similar to sylgard (viscosity & cured hardness). 2lb kit costs $43.20. So about half the cost.

I do not believe this compound is UV stable and would yellow over time unlike Sylgard 184 and Qsil 216

Sizz
09-08-2010, 03:01 PM
I do not believe this compound is UV stable and would yellow over time unlike Sylgard 184 and Qsil 216

How do you know this?

knowyourplanet
09-08-2010, 04:16 PM
How do you know this?

Hi, I have spoken to Silicones INC technical support, the product P-4 is not UV resistant and not designed with UV resistance in mind (or PV application) and will yellow in time.

For further details about qsil 216 and its applications, see the following PDF.

http://www.acc-silicones.com/_assets/pdfs/applicationsheets/acc%20photovoltaics%20aplication%20sheet.pdf

Qsil 216 was specifically developed for high intensity solar potting to optimise the output of the cells.

tlgoose
09-09-2010, 06:56 AM
Longwolf,
I had issues with my pour(cs).I made my aluminum frame and sealed lexan to it with clear seal and weights.Then i sealed all edges.I bought 4 tubes of cs and mixed it well.Then i poured my sc.I then used a foot massager under the table and vibed all the air pockets out.Seemed to work rather well.When i checked on it an hour later,it leaked out about a tubes worth from 2 sides.At this point i don`t dare move it at all until it`s firm.I`m hoping i`ll be able to remove most on the sealant from the front face.If not it looks like i`ll be able to read the daily news through my panel.Lesson well learned.Seal the living daylights out of the frame before pour.If you think it`s sealed,seal again.I did use 50/50 mix and i think the mineral spirits broke down the sealer for the face plate.I`m glad it was a small panel but i`m still out alot of $$.When it drys i`ll repost the full outcome.
tlgoose

Minnesota
09-09-2010, 08:21 AM
One thing I have not heard discussed is spraying the cell strings thoroughly with a quick-drying "harmless" silicon spray like http://www.3inone.com/products/silicone-spray/ then using a dab of PV 804 to hold the cells to a rear piece of sturdy glass, lexan, or the plastic sheet of your choice. Top sheet of glass or lexan held to the compatible back piece with PV 804. Small airgap, but ventilate it like an aircraft window with a small back vent hole if necessary. Cell and conductor corrosion avoided at virtually no cost.

longwolf
09-09-2010, 10:27 PM
Longwolf,
I had issues with my pour(cs)..........

Sorry to hear it tlgoose.
Do you think you can just pour another coat over the back?

------------
My panel has been up on my van for 3, maybe 4 weeks now.
We just had a couple of days of rain here, then a couple of dry days.
I decided to check my panel. There were no signs of vapor in in the large bubbles between the cells and glass. I went to lift the panel so I could check the backs of the cells. One of the power wires had stuck to the CS near the center of a cell. When I tugged on it, a 1/4 inch piece of the cell broke. Looking are the front of the panel, I had a new bubble were the cell had broken.
It turns out that the CS under the cells is still very liquid, I could even smell the mineral spirits in it. Looking at the tops of the cells you can see that there's a 1/2 inch wide ring around each of them where the cells have darkened/ discolored. I believe the darkened area is were the CS has dried.
It doesn't seem to have harmed the panel. In fact I took my highest reading yet, 20.2 volts @ 7.9 amps. But it does look like it will take months for the CS to dry completely.

longwolf
09-09-2010, 10:30 PM
One thing I have not heard discussed is spraying the cell strings thoroughly with a quick-drying "harmless" silicon spray like http://www.3inone.com/products/silicone-spray/ then using a dab of PV 804 to hold the cells to a rear piece of sturdy glass, lexan, or the plastic sheet of your choice. Top sheet of glass or lexan held to the compatible back piece with PV 804. Small airgap, but ventilate it like an aircraft window with a small back vent hole if necessary. Cell and conductor corrosion avoided at virtually no cost.

Hum, interesting idea. If you try it, let us know how it goes.

Mike90250
09-10-2010, 01:48 AM
One thing I have not heard discussed is spraying the cell strings thoroughly with a quick-drying "harmless" silicon spray like http://www.3inone.com/products/silicone-spray/ then using a dab of .......

This is a LUBE, it is not a sealer. Once any silicone lube gets on ANYTHING, it will act as mold release, and no glue of any kind will ever stick to it.

That's why silicone lubes are banned from jet aircraft, it will actually creep under good paint, and lift it off the base metal. Corrosion sets in, and it can never be cleaned and repainted.

tlgoose
09-10-2010, 06:32 AM
As soon as it sets up enough i`ll try a second pour.It seems to have stopped leaking for now but i`ve lost about a tube and a half during that time.I ended up suspending it on sockets to get it up off the table.I think next panel i`ll try one tube at a time and let it set longer between pours(if i do another).I`ve got enough $$ into this where i could almost buy a panel outright(around $80. into it).

tlgoose
09-14-2010, 06:51 AM
Anyone trying to encapsulate with clear seal.What i`ve discovered is when you pour do a small pour just enough to cover cells.I poured about 4 tubes(15"x32" panel) mixed 50/50 and the cells kept rising up out of the cs over time.So do low pour and let dry first before adding any more to it.It does dry real clear.I`m on my second pour(3 more tubes@ 2/3 mix).I`ve got it on a glass top table so i can see through it.The mineral spirits soften up the first pour quite a bit and i have to keep pressing the cells back down.Very few bubbles noted but not completely dry yet and can still press them out.On the first pour when the cells rose it snapped off my soldered wire on the buss wire.Luckly i left enough wire on the end of the bus to clean it and resolder and then sink it into the cs.
tlgoose

DeltaFox 25
09-14-2010, 05:30 PM
)

Mineral Spirits, also called Stoddard solvent [CAS 8052-41-3][1], is a petroleum distillate commonly used as a paint thinner and mild solvent. Outside of the United States and Canada, it is referred to as white spirit. In industry, mineral spirits is used for cleaning and degreasing machine tools and parts. According to Wesco, a supplier of solvents and cleaning equipment, mineral spirits "are especially effective in removing oils, greases, carbon, and other material from metal." Mineral spirits may also be used in conjunction with cutting oil as a thread cutting and reaming lubricant.

I think your mineral spirits has a good chance of hurting your cell's

longwolf
09-14-2010, 07:20 PM
)

I think your mineral spirits has a good chance of hurting your cell's

So far my cells have been in the CS, cut with mineral spirits, for over an month
and there hasn't been any degradation in the panels output. But I'll post updates as I find them.
My biggest concern is it's fairly low heat tolerance. But so far that hasn't been a problem either.

DeltaFox 25
09-14-2010, 09:47 PM
irritant. It also receives a class 3 flammability rating; once its relatively high flashpoint is reached, mineral spirits will burn just like any hydrocarbon-based solvent, thereby emitting dangerous toxins

This is mineral spirits

longwolf
09-15-2010, 10:35 AM
..... mineral spirits will burn just like any hydrocarbon-based solvent......

That I can't argue with :)

DeltaFox 25
09-15-2010, 01:07 PM
Don't you think that it would be bad for your cell's

Mike90250
09-15-2010, 01:25 PM
Don't you think that it would be bad for your cell's

maybe not, alcohol is a hydrocarbon, and it's used to wash cells clean at the factory.

longwolf
09-15-2010, 10:11 PM
Don't you think that it would be bad for your cell's

Well, if I set fire to them, sure.
But hopefully it won't come to that :)
As far as it eating them, we'll just have to wait and see.

wjgrisham
09-17-2010, 04:58 PM
This is all kind of new to me be the only way to find out is through study and ask.
What is a good material to use for the front cover for your solar panel? I do not want to use something cheap that will not hold very long or crack easily?
Thank you,Bill

longwolf
09-18-2010, 12:07 AM
This is all kind of new to me be the only way to find out is through study and ask.
What is a good material to use for the front cover for your solar panel? I do not want to use something cheap that will not hold very long or crack easily?
Thank you,Bill

Personally, I'd use regular 1/4 inch tempered glass.
I used low iron tempered on this panel, but came to the conclusion that it's not worth the added expense.
I have a thread about it here:
http://www.solarpaneltalk.com/showthread.php?t=2230

longwolf
09-18-2010, 12:10 AM
We had more rain and then it dried up again. So I checked the back of the panel. It looked good except for one of the solder pads that is showing a bit of black corrosion. Looking closer I could see that a bubble had popped above the pad leaving a hole.

So I took some alcohol (it's pretty much what you use to remove water from a gas tank), poured it over the hole and let it evaporate. Then I covered the hole with a piece of electrical tape.

The CS on the back of the panel is thin so I also covered any solder 'bumps', that might work their way through, with pieces of tape.
Next I took some extra wide, heavy duty Reynolds wrap and used some spray on adhesive to cover the back of the panel. It took two pieces of foil to cover all the cells so the center section has about 10 inches of overlap.

Now this reminds me of when I was a kid and wrapped a battery in aluminum foil, so next I tested for continuity between the foil and the positive/negative leads. Lucky for me, looks like I got away with it.
I couldn't get the foil on without quite a few small wrinkles, so I took the last couple of ounces of clear seal and ran a thin bead over the edges of the foil.

Hopefully, this panel will work for a good long time now, but the thinned CS at the center of the cells may never dry :)

tlgoose
10-02-2010, 03:44 AM
Here`s my update.
I put my panel in the Florida sun yesterday morning.It got quite hot.I had 2 very small bubbles in the cs.By mid afternoon the little bubbles(not even the size of a 16 penny nailhead)became 3/4 of the panel.Unable to work them out.Dollar for dollar it would have been cheaper for me to use slyguard then clear seal.unlucky for me, panel unusable.Lucky for me i found a flexible panel on Craigslist for $20.00.
tlgoose

longwolf
10-02-2010, 10:30 PM
Here`s my update.
I put my panel in the Florida sun yesterday morning.It got quite hot.I had 2 very small bubbles in the cs.By mid afternoon the little bubbles(not even the size of a 16 penny nailhead)became 3/4 of the panel.Unable to work them out.Dollar for dollar it would have been cheaper for me to use slyguard then clear seal.unlucky for me, panel unusable.Lucky for me i found a flexible panel on Craigslist for $20.00.
tlgoose

I hate to hear about your bad luck.
But if you don't seal or dam the panel well first I don't think the slyguard will work any better for you.

tlgoose
10-02-2010, 10:48 PM
It did finally seal on the front.I`ve had it laying face down for quite some time.Center was alittle plyable but when turned over (for several days)it held tight.I sealed the back with caulking (3 tubes)and plywood then caulking again.Everything seamed fine and it had been sitting outside for awhile(under screened room),I moved it out to diect sun.It got real hot.I think maybe the lexan expanded or something to that effect.Well it was worth a shot and a good experiment,just a poor outcome.I still have some single cells and i`ll try something different next time,just in a smaller size.
tlgoose

charlie_ruizpr
10-07-2010, 02:45 AM
Is it possible to use Polyurethane Construction Adhesive in between the two glasses?

longwolf
10-07-2010, 07:40 PM
Is it possible to use Polyurethane Construction Adhesive in between the two glasses?

I don't know anything about that material.
But I'm only using one piece of glass, the CS and then aluminum foil over the back.

charlie_ruizpr
10-13-2010, 03:31 AM
I don't know anything about that material.
But I'm only using one piece of glass, the CS and then aluminum foil over the back.

This is the site that may explain what the product is http://www.liquidnails.com/products/product.jsp?productId=54

I have used it to seal automobile glass and have seen auto glass shops use this stuff all the time.

Layout1
10-16-2010, 02:55 PM
Well how did the liquid nails work out for you?

Thanks
Dave T

longwolf
10-16-2010, 09:24 PM
Well how did the liquid nails work out for you?

Thanks
Dave T

The Clear Seal I used is a liquid nails product.
All things considered, it turned out well for my first shot at making a panel.

I don't know about the one that Charlies talking about.
Two things I'd want to know about it are, how clear is it and what's the temp range?

charlie_ruizpr
10-18-2010, 12:47 AM
The Clear Seal I used is a liquid nails product.
All things considered, it turned out well for my first shot at making a panel.

I don't know about the one that Charlies talking about.
Two things I'd want to know about it are, how clear is it and what's the temp range?

It is black and is for automobile use, I have seen it applied on cars at auto glass shops and on mine particulary and I kno it seals well, don't kno the temp range, but I do kno that it does not crack automobiles glass. It is even used on engine mounts to stiffen them up.

longwolf
10-19-2010, 07:03 PM
Well, you couldn't use it for encapsulating the cells then.
Encapsulation not only protects the front and backs of the cells, it also can increase the amount of light that gets to the cells.
I explained that in an experiment I described earlier in this thread (I believe).


It is black ....

Layout1
10-19-2010, 09:43 PM
The Clear Seal I used is a liquid nails product.
All things considered, it turned out well for my first shot at making a panel.

I don't know about the one that Charlies talking about.
Two things I'd want to know about it are, how clear is it and what's the temp range?

Well does that mean it leaked a little bit for your first one or what? Like to know what all those things considered might be. Like did it do the job? What tests if any have you conducted on the panel, etc.

Thanks
Dave T

longwolf
10-20-2010, 10:21 AM
Well does that mean it leaked a little bit for your first one or what? Like to know what all those things considered might be. Like did it do the job? What tests if any have you conducted on the panel, etc.

Thanks
Dave T

Here are a couple of posts were I describe some mistakes I made and what I did about them.
http://www.solarpaneltalk.com/showpost.php?p=12687&postcount=52
http://www.solarpaneltalk.com/showpost.php?p=12904&postcount=77

And here's a post that shows how the panel is doing.
http://www.solarpaneltalk.com/showpost.php?p=12081&postcount=28

Need4Speed
11-02-2010, 07:33 AM
[QUOTE=smoothbrad;11737]A 2-part platinum-based (Addition cure) room temperature vulcanizing (rtv) silicone rubber is most suited because during the cure cycle this material will not exude any by-products such as acetic acid and alcohol, both of which are associated with tin-based silicones.

Platinum based systems do not need to be thinned out with any solvents either, and are considered to be archival in the sense that they will not modify or change over time. Solaris

the pu man
11-03-2010, 12:04 PM
Hello All, I have been reading this thread with interest. I have been involved within the thermoset resin systems business now for some 17 years and have begun development projects with a number of major solar players and it appears you guys may need some help! Why everyone has chosen to use silicone is somewhat strange. Silicone or at least the 2pk silicone systems for electronic and electrical gives one major benefit over standard thermosetting systems in that it has a high working temperature range IE it can run from - 60 to 200 deg c. We currently produce a range of Polyurethanes, a range we have produced for over 20 years which are clear, exhibit excellent UV stability (certainly higher than that or comparable to silicone -

russ
11-03-2010, 01:07 PM
Welcome to the pu man!

A number of people will be very interested in your knowledge on the sealing topic!
Again - welcome,
Russ

Jason
11-03-2010, 01:14 PM
I agree with Russ.

It's nice to have someone in a different industry with a different POV.

Should be interesting.

Thanks for registering and I look forward to your posts!

Need4Speed
11-03-2010, 04:03 PM
Why everyone has chosen to use silicone is somewhat strange.

What about curing agents releasing acids, or is that only in epoxies?

the pu man
11-04-2010, 05:55 AM
Hi Need for Speed,

Curing agents releasing acids should not occur when using a PU. The reaction is between the OH of the Polyol and the NCO 2 in the Isocyanate. You can drive the reaction through catalyst addition in the Polyol but this is general as extremely low % of the mix and done during the manufacture rather than you adding before mix.

Essentially the PU reaction is exothermic which means it requires nothing but the two parts at the correct ratio - this is the important bit, you go off ratio you get overdose on one of the parts which leads to poor cure and sticky mess. This is different from Silicone which uses a catyalyst to drive the reaction and often the more or less you use the quicker or slower the reaction. Epoxy is similar to Polyurethane however it tends to be more forgiving, although they are quite agressive chemicals which usually are denoted as corrosive which I think may be where you are seeing problems with Acid.

Again reffering to the above the one thing to watch on PU is a potential secondary reaction which is Water IE H20. In combination with the OH and NCO2 it produces CO2 so gas bubbles. You are probably sitting on this reaction as you read this!!

Looking at what is trying to be done water in locality is a big no no anyway.

The points to consider in this application are
1. Adhesion to glass or polycarbonate sheet (seems most people use glass but there is a grade of Polycarbonate - makrolon from Bayer which is a really tough clear UV stable sheet with fantastic impact resistance. If you have a dvd then thats the same stuff). We currently have clients making bullet proof and hurricane resistant glass which uses the clear polyurethane as the interlayer (very similar to this application in some respects).
2. Adhesion to solar cell
3. impervious to water
4. capable of thermal cycling without loss of adhesion or cracking
5. UV stable
6. Easy to mix and pour
7. none reactive during and after cure - this is why you can only consider the exothermic cure products and why if you try a one part this is going to lead to issues.

In honesty there are so many types of Epoxies and they can differ widely in ingredients so it may be that the issue you refer may well be specific to a certain type of Epoxy due to the constiuent ingredients.

Need4Speed
11-04-2010, 06:23 AM
Again reffering to the above the one thing to watch on PU is a potential secondary reaction which is Water IE H20. In combination with the OH and NCO2 it produces CO2 so gas bubbles. You are probably sitting on this reaction as you read this!!

Looking at what is trying to be done water in locality is a big no no anyway.


Are you saying liquid water should be avoided during the casting process of the PU, or should ambient air humidity be low?

the pu man
11-04-2010, 07:02 AM
Both.

The reactive ingredients in 2 part Polyurethane are hydroscopic. if you look at each individual consituent the Polyol will uptake moisture but you dont know its there until you mix it and then you get Carbon dixoide gas formation. In the Isocyanate it will react to form a very hard UREA crystal, again gassing as it forms these crystals. This is why in most 2 part polyurethanes once you open the container you need to use it all up.

During the cure the hydroscopic nature gradually reduces as the polymerisation occurs.

If you are in a high humidity environment, the open time is long and the cure thinkness is thin film these can lead to atmospheric contamination, which appears as bubbling.

If you were going to use it for solar cell you would find that you can process much quicker and use a little heat after you have poured it to help speed up the cure and stop any potential contamination from atmospheric moisture.

Bear in mind this is worst case. It is not a case that as soon as you open to atmosphere you have a problem.

Any liquid water is an absolute no no however there should be absolutely no reason why you would want to start adding water to the products nor any reason why there would be water present on your solar cells, unless of course you want to make a foam.

Need4Speed
11-04-2010, 05:14 PM
What shore hardness should I be looking for in a PU product? I know this is not your product but maybe you can provide some advice:

I can get Smooth-On's Clear Flex 50 (PU rubber) or Crystal Clear 200 (PU plastic) from a local supplier. I'm leaning towards Clear Flex 50 because it has lower shore hardness (50A vs 80D). Also the viscosity is lower (250 cps vs 600 cps). Clear Flex 50's shrinkage is specified @ 0.0015 in./in.

Any reason I should not be using these products?

the pu man
11-05-2010, 05:49 AM
The crystal clear 200 is a no no. It is way too rigid. The clear flex 50 is more appropriate.

Hardness is measured on a given scale. It begins on the OO scale which is for gels and foams and then moves to the A when it moves above a gel like state. There are other scales in between but generally our industry uses 00 A and then D.

00 - foams and gels
A - gel to semi rigid
D - semi rigid to rigid

For example and 10 A material will be skin like in hardness, soft and squidgy.
60 - 65 A roughly a car tyre
90 - 95 A standard tap washer
90 D - Glass, bone

The scales actually overlap so somethinG which is say 90 A will also appear on the D as approximately 35 - 40 D.

Silicones register in the A scale and are never rigid so any alternative needs to replicate this hardness.

Soft material is very importatnt as it allows expansion and contraction during temperature cycling. Imagine that you have several differing materials / substrates each one reacting very differently to temperature. If you have too many mismatches then you will risk losing adhesion and or breaking the cells or even the glass. If you get the delamination of the resin system you will end up with water penetration.

Going to a sfot material, even though this will have a much higher thermal expansion and contraction charateristic, will actualy negate the issue. They tend to place low stess during cycling becuase they are soft, they also have good elongation which allows the material to expand and contract, to little elongation IE rigid and it cracks - pretty standard technology in the electronics and electrical industry when dealing with PCB boards and delicate components - go to rigid and it the encapsulant will literaly rip the components from the board during cycling.

The 50 would be my choice as it is low shore rubber like with good elongation. However I dont know what the adhesion to glass would be like. It mentions in the MSDS use of plasticisers within the Polyol. These can cause issue if they are used to soften. Some do not actually react in the system and can migrate over time, they can also act as a release agent. I would give it a go on a small area. Get your glass and run a test area to see if it sticks, obviously make sure the glass is clean and you use a cleaner which is not going to put any greasy film onto it.

In terms of shrinkage you are pouring in thin film. Shrinakge is linear and is based on mass and temperature - remember these systems are exothermic reaction IE the bigger the mass mixed, the higher the temperature the faster and more extreme the reaction between the two chemicals. When you pour in thin film the shrinkage would not be an issue, its also another reason to use soft material as rigid materials will always shrink more. Bear in mind however that this system has a pot life of 25 minutes from the start of mixing. Make sure you are prepared. Also bear in mind that if you go and mix this system agressively you will put bubbles into it. Another tip is to make sure you decup into a new mixing vessel after the first mix. The biggest failure through hand mixing products is unmixed material splashed around the sides of the vessel being incorporated into the mix when you pour. If you mix in one vessel decup and then remix in a new vessel you wont run the risk of unmixed incoporation. Another trick is after you have poured the material get a hairdryer and blow the surface of the liquid. The heat from the hairdryer will expand the bubbles and pop them.

One word of warning - I can not clearly see the exact type of Isocyanate being used here for the part A. Some can be particularly toxic. We dont tend to use these unless we have to but I do know a lot of companies still sell these types. There is also mercury in this product which is pretty much close to being banned across the world so be aware that this product may change in the next couple of years.

Unfortunately we are a big manufacturer so we dont do small lots of material. I will see if one of our distributors is prepared to stock and market our system as we do have a number of distrbutors who market to specific industries.

Let me know how the Smooth on fairs and if you need any more help.

the pu man
11-05-2010, 05:54 AM
Sorry forgot to mention that you need to check out the recommend working temperature range of the system to ensure it is compatible.

dlmcbm
11-08-2010, 01:05 PM
Has anyone tried the Sashco "through the roof" yet? If not can anyone tell if its good to use or not. I can buy this local and $30 a gallon sounds great to me.
http://www.sashcosealants.com/home_improvement/Through_The_Roof.aspx
Thanks

the pu man
11-09-2010, 04:34 AM
the sashco product is a sealant for use in thin film cure applications. It will probably not cure very well if you try to get any build height on it. It may work for sticking cells to glass but for back encapsulation I think you will struggle.

RifRaf
11-18-2010, 04:51 AM
has anyone tried any of these products on some panels yet? any pictures or test results? all sounds good but would really like to see some panels made this way

the pu man
11-19-2010, 09:03 AM
Hi Rif Raf we are making up some panels over the next two weeks. We have two products being tried out. We also have a UV weathering chamber so we are going to put panels in at highest UV setting with water program every hour. It gets real hot as well at 65 deg c. Will post when we have some results. We will be shooting vids etc for the build.

Aqua
11-23-2010, 05:47 AM
pu man
Am in the UK and have two 200w panels to make is there any way I can help test the products you are trying.

the pu man
11-24-2010, 09:29 AM
Hi Aqua we have already begun the test and trial process and would be concerned to have to many variables in terms of guinea pigs! Give me a couple of weeks, if you are in the UK then snow is on the way and not much chance for making that solar energy anyway!! I will see how things progress and then I will update here if we need more testers. The testers we have are purely those involved in builds previously but they dont get to keep the panels. All panels are going to be tested to oblivion through our UV weathering chambers and actually be pulled apart by our tensiometers to test adhesive strengths before and after. IE panels will be sacrificed for the cause.

Aqua
11-24-2010, 11:03 AM
Ok am looking forward to hopefully favourable results

LeeP
12-01-2010, 10:18 PM
The discussion about encapsulation materials reminded me of an economical technic. It is a paper on fool proof method that makes a lot of sense to me. I'll be using it myself shortly. Find it here (http://www.ases.org/papers/103.pdf).

russ
12-02-2010, 01:01 AM
Hi LeeP - Welcome to Solar Panel Talk!

The link to the pdf file about laminating PV cells is very interesting.

Well done!
Russ

RifRaf
12-07-2010, 04:30 AM
hi LeeP , Aqua and The Pu, how are the tests going? still have a few panels to make and eager to see some of the results

dlmcbm
12-27-2010, 07:03 PM
Well I tied the "through the roof" product. I will have to say that this is my first attempt at making solar panels. It seems to work well just fighting a few problems. The stuff is very thick.
I made the first panel by brushing some on the back then laying them back side down on my backer Plexiglas. then I poured some over top of them and put the front piece on. My problems hear are 1. I did not pour enough in so I had a lot of air pockets. 2nd It made it a sealed box then so no air can get to it to cure it and harden.
I made the second panel like you normally would with the cells face down. I thinned the roof patch with mineral spirits(paint thinner) This did work a lot better but it was still to thick to flow totally under the cells so I had all the edges sealed but not the whole face of them. This was going well I only had a few small cracks in 2 cells till I dropped it. (Whoops) I was not happy now because it almost shattered about 4 or 5 cells.
The biggest problems I had are this stuff takes A VERY LONG TIME to dry. Its even worse when its only 25 degrees outside. It puts off bad fumes to so you dont want it in your house. They do say 1 week to fully cure and I did jump the gun there. The panel that I thinned with paint thinner I think that damages the cells. Most of them that are not covered the blue has become dull like the chemicals have done something to them. the one without the paint thinner looks fine. I was thinking of trying to thin it with alcohol. does anyone know what will or will not hurt the cells???

Bigbirdd
01-16-2011, 08:21 PM
I use dual pane windows I buy them from habitat for humanity i use 100% silicone the last tube were white Vin the summer after tabbing me sells together I can make one day I lay 6by6 seal around cells seal the edge of glass i use white paneling lay white side down let it dry for a couple hours paint the back side with indoor/outdoor MINWAX HELMSMAN spar urethane.

http://www.solarpaneltalk.com/images/mysolarpanels.jpg

these are solar panels in my array the top two long ones I were my first two panels I built with cheeped sells from evergreen yhe one left bottom are single pain window one to right under long panels I built last summer duel pain glass
the rest are single pain which I will replace as I build more as they go bad. I run a regular refrigerator and lights Iam trying to run 12volt only. During summer I can run satellite during the day I also have a generator I charge the battery at night as you know we get 4 hrs of usable sun light

Bigbirdd
01-16-2011, 11:48 PM
I use dual pane windows I buy them from habitat for humanity i use 100% silicone the last tube were white Vin the summer after tabbing me sells together I can make one day I lay 6by6 seal around cells seal the edge of glass i use white paneling lay white side down let it dry for a couple hours paint the back side with indoor/outdoor MINWAX HELMSMAN spar urethane.

http://www.solarpaneltalk.com/images/mysolarpanels.jpg

these are solar panels in my array the top two long ones I were my first two panels I built with cheeped sells from evergreen yhe one left bottom are single pain window one to right under long panels I built last summer duel pain glass
the rest are single pain which I will replace as I build more as they go bad. I run a regulsr refrigerator and light during summer I can run satellite guring I also have a generator I charge the battery at night as you know we get 4 hrs

The duel pain window cost $5 4by8 paneling about $8 Thw urethane $25 I can get 3pannels out of it silicone on sale at ace for $3.39 most expensive the solar cells I get them on Ebay

uhurr
01-17-2011, 10:02 AM
Well , Your way is different , end inexpensive, I liked,, do you have pictures step by step?., that will help a lot, what kind battery you used?,how old is your oldest panel ? still it working good? god bless you and tank you .

Bigbirdd
01-17-2011, 08:48 PM
I use 10 6volt golf cart battery giving me 5,12 vol tiers at 105 amp hour and if I'm doing the math right I have 525 amp hrs total. I use a Macnum ms2812 inverter/charger and a Tristar60amp charge controller. Its winter so my production is down I have plans to build 6 more 36 cell panels 18v 63w 3.5 A. My oldert panels are the two long ones I built three years ago out of chipped cells.

Bigbirdd
01-18-2011, 12:07 PM
I would like to know if blocking diodes are needed with a charge controller . and would the panel feed back to each other if one wasn't punting out the sane voltage, like a shadow over part of the array.

Mike90250
01-18-2011, 01:17 PM
I would like to know if blocking diodes are needed with a charge controller .
None needed




and would the panel feed back to each other if one wasn't punting out the sane voltage, like a shadow over part of the array.
Panels in parallel need to be fused so backfeed can be limited
Panels in series, shade will limit the total current to the shaded portion.

Shade is bad.

Bypass diodes (mfg internal to the panels) can help, but the diodes can be burned out and fail.

Bigbirdd
01-19-2011, 10:21 PM
None needed



Panels in parallel need to be fused so backfeed can be limited
Panels in series, shade will limit the total current to the shaded portion.

Shade is bad.

Bypass diodes (mfg internal to the panels) can help, but the diodes can be burned out and fail.

I build my own solar panels 18volt 63 w 3.5a all my panels run into a combiner block I made. I was using diodes but was loosing a volt or two I was reading another thread where some talk about capacitors is this something I could wire in before the combiner.

Bigbirdd
01-20-2011, 01:29 AM
Here are photos of my panel in this other thread:

http://www.solarpaneltalk.com/showthread.php?3167-My-Homemade-Solar-Panel-Project

wayhopper
01-22-2011, 06:30 PM
I have been reading the forum for several days.

Sylgard or it European counterpart seem to be the ideal substances to use in this encapsulation process. The problem is the high cost of the Sylgard, which will add a very substantial percentage to the cost of the panels.

Here is a possible solution. Sylgards primary usefulness comes from its UV resistance and its ability to dry crystal clear and remain clear for a very long period of time.

These properties however are only necessary on the front of the cells. They are not required on the back except as an air and water seal.

Why not use the Sylgard on the front of the cell only, paint a thin film on the surface of the cells on an entire stringer and then lay the cells on the glass in a rocking motion until they are flat. Work hard to keep the bubbles out. Let them dry with weights to hold the entire string completely flat on the surface of the glass, perhaps use the L brackets of a future panel to do this.

But now the backs of the cells are not sealed. Use another cheaper substance to seal the back side where UV and clairity are not required. Here almost anything will work, plastic, paint, varnish or many other substances. Take great care not
not to choose a substance which will corrode the wires and connections connecting the cells. This might streach a quart of Sylgard so that a quart could concievably complete three or four panels. This would indeed be a major saving in the construction of the panels.

Please comment on these ideas, give me feedback before I waste money on a panel which will develop problems.

Here is a question I would like to have answered. What would be the effect of Sylgarding the cells to the glass untabbed? Would the heat required to solder them after the cells were attached damage the Sylgardf? This would be an effort to eliminate warping of the cells caused by the soldering action.

wayhopper

Mike90250
01-22-2011, 06:36 PM
.....
Here is a question I would like to have answered. What would be the effect of Sylgarding the cells to the glass untabbed? Would the heat required to solder them after the cells were attached damage the Sylgardf? This would be an effort to eliminate warping of the cells caused by the soldering action.

How do you attach the tab wire to the fronts ?

Possibly tab front an back of each cell, leaving a short stub, clean cells, then "dip" each cell 100 % into sylguard? That would coat each one, you could solder the tabs, and then encapusulate the rest with nearly anything clear, as long as the initial sylguard dip was good.

Calgirl
01-23-2011, 06:53 AM
Why not use the Sylgard on the front of the cell only, paint a thin film on the surface of the cells on an entire stringer and then lay the cells on the glass in a rocking motion until they are flat. Work hard to keep the bubbles out. Let them dry with weights to hold the entire string completely flat on the surface of the glass, perhaps use the L brackets of a future panel to do this.

But now the backs of the cells are not sealed. Use another cheaper substance to seal the back side where UV and clairity are not required. Here almost anything will work, plastic, paint, varnish or many other substances. Take great care not
not to choose a substance which will corrode the wires and connections connecting the cells. This might streach a quart of Sylgard so that a quart could concievably complete three or four panels. This would indeed be a major saving in the construction of the panels.


wayhopper

Why not do all solder work, then paint back (blue side) and the tabs with Sylgard and let dry BEFORE laying down on the glass? Make certain to cover tab wires. For added insurance and to make the cell string stick to the front glass, you could run a line of Sylgard on glass where cells will be prior to placing the cells on the glass. After dry, paint/spray backside with whatever substance suits your fancy. Just make sure to cover all wires, all the way around.

Check string with volt/amp meter at each step.

the pu man
01-24-2011, 04:24 AM
There is one major flaw with this process. If you simply use the Silicone on the front and then look to use something cheap on the back how are you going to 'adhere' another encapsulant to the silicone? Very few products actually adhere to silicone. You also run the risk dependent on the other material of all the problems listed prior IE making sure you pick something that is not going to react with the silicone, making sure the expansion and contraction charateristic of the 'other encapsulant' is similar to ensure you dont get a split line between the two materials as the panel expands and contracts with temperature ranges. If a split line does occur then it will actually draw moisture in as it expands and contracts.

Water will always find a way through so having an interlayer of two differing types of materials runs a far higher risk of failing than sticking to just one. Also remember that contary to popular view on silicone they are actually porous so the thinner the coating the higher the potential the moisture will ingress through.

Coming from an electronics and electrical potting and encapsulation background I have never seen any success in trying to use silicone in conjunction with another material. You are simply adding a variable into the process which opens up far more knock on issues than if you had just spent the money in the first place.

Calgirl
01-24-2011, 05:23 AM
Very good point....thanks.

elect41
01-24-2011, 08:55 PM
Hey guys,

Want some advise,solar encapsulation product aeromarine300-21 its suppose to be self leveling
http://www.jgreer.com/pages/pdf/30021-tds.pdf

Bigbirdd
01-25-2011, 12:18 AM
There is one major flaw with this process. If you simply use the Silicone on the front and then look to use something cheap on the back how are you going to 'adhere' another encapsulant to the silicone? Very few products actually adhere to silicone. You also run the risk dependent on the other material of all the problems listed prior IE making sure you pick something that is not going to react with the silicone, making sure the expansion and contraction charateristic of the 'other encapsulant' is similar to ensure you dont get a split line between the two materials as the panel expands and contracts with temperature ranges. If a split line does occur then it will actually draw moisture in as it expands and contracts.

Water will always find a way through so having an interlayer of two differing types of materials runs a far higher risk of failing than sticking to just one. Also remember that contary to popular view on silicone they are actually porous so the thinner the coating the higher the potential the moisture will ingress through.

Coming from an electronics and electrical potting and encapsulation background I have never seen any success in trying to use silicone in conjunction with another material. You are simply adding a variable into the process which opens up far more knock on issues than if you had just spent the money in the first place.

Hi this bigbirdd All I have read about encapsulation is done on the back of the cells. I use duel pane glass windows and mount my cells seal the back.during hot Idaho summers I have on voltage loss. So how will encapsulation benefit me.Right now i don't encapsulate my cells I run silicone on the cells not crossing the tabbing . I then silicone the outer edge place backing to silicone area than seal backing with urethane. Its work so far I have a panel I built last year its been through rain ,snow .

the pu man
01-25-2011, 06:06 AM
Hey guys,

Want some advise,solar encapsulation product aeromarine300-21 its suppose to be self leveling
http://www.jgreer.com/pages/pdf/30021-tds.pdf

This product would give far better UV stability over a standard Epoxy clear system agreed however if you check through the data it is a rigid system - a major no no. If you used this type of system during cycling it would crack and probably crack the cells as well. Any encapsulant used needs to have flexibility so that it can expand and contract without causing stress fracture.

elect41
01-26-2011, 04:58 PM
Thanks again guys,

Your information has helped me,it seems that sylgard its the best choice.
Very helpfull

Thank you.

grayski41
01-27-2011, 03:03 AM
Hi all,
im new here an to solar panel construction, I have made one panel with no encapsulation and now busy making 6 more, Alliminium frame and backing with plexiglas front, I intend to lay the cells in the frame held in place with a little silicone and then paint the cells with slygard or equivilant, I have been told i can reduce costs and bubbles by thinning the slygard with xylene and only painting a thin layer on the front only, and use a cheaper acetoxy silicone thinned with xylene on the back of the cells before placing in the frame... any ideas/ thoughts would be welcome

russ
01-27-2011, 04:50 AM
Hi grayski41 - Welcome to Solar Panel Talk!

One of our DIY types should be along with a comment before long.

Russ

Bigbirdd
01-28-2011, 10:13 PM
You talked about fused panel how do I do it. or rather what do I use.

Jeffc
01-29-2011, 03:00 PM
I came across this forum while looking for a cheap way of encapsulating my panels.---Glad I did!

I have five 60W panels up on my roof at present ,two have been up for about 18 months ,three for about six months.

None have any encaptulation. ( Gasps I hear ) It was only supposed to be temporary , but I left them up there !

I needed a system in place in order to apply for ROC before the 31/3/2010 deadline.

All the panels are holding up well despite braving all the elements , although there is a lot of condensation in the panels which is not good.

I was encouraged to see the video with the guy applying Silgard , but was dismayed at finding out the cost.

I thought the bulk of the cost of making the panel would be the cells , now at approx

Calgirl
01-30-2011, 02:48 PM
Why not dip the entire string in Sylgard, and then hang it up to dry by the tab wire? That way you cover the entire cell and almost all wiring at much less cost than painting the glass front and then painting the back of the cells and wire, or pouring the encapsulant. A little Sylgard touch-up after strings are re-located and re-soldered in the panel and you have a panel of cells and all wiring well protected.

Another approach would be to lay the dipped string down almost immediately on the glass so that you have a seal between the glass and the cells to prevent moisture getting between the Slygard protected cells and the glass.

Since the Sylgard covering on the backside of the cell would be pretty thin, I would apply a thin cover on the panel back....one that allows for heat dissipation and air circulation. The backside cover is only to give a little mechanical protection to the cells, etc.

DeltaFox 25
01-30-2011, 04:27 PM
Have you ever worked with sylgard???? I have and it's a very thick substance.
I don't think you could coat them and hang them up to dry. and the wireing would be weakend also. Good luck to you if you can do that..Why don't you put the sylgard down then put the cells down then cover the rest with the rest of the sylgard. do this all at once. O Don't forget the backing.

Jeffc
01-30-2011, 05:12 PM
From Datasheet-

POLYSULPHIDE SEALANT is a one component, gun applied, synthetic rubber based sealant which cures by absorption of atmospheric moisture to form a permanently flexible seal. It is suitable for use within the construction industry on all joints where above average repeated movement is encountered over a wide temperature range. It provides outstanding resistance to weathering and chemical attack from solvent, alkalis, dilute acids, oils and grease.

This is the stuff that is used to seal double glazing units.


How about applying a bead of this around the perimeter of each cell onto the glass. Notice it cures by absorption of atmospheric moisture so any moisture between the cell and glass will be absorbed in the curing process.

Here is a link to the data of a product sold in UK.

http://www.kingfisheruk.com/specs/data/polysulphidesealantpds.pdf

It has very good U/V resistance and 20+ yrs service life. Oh and it

Calgirl
01-31-2011, 10:41 AM
[QUOTE=Jeffc;18257]From Datasheet-

POLYSULPHIDE SEALANT is a one component, gun applied, synthetic rubber based sealant which cures by absorption of atmospheric moisture to form a permanently flexible seal. It is suitable for use within the construction industry on all joints where above average repeated movement is encountered over a wide temperature range. It provides outstanding resistance to weathering and chemical attack from solvent, alkalis, dilute acids, oils and grease.

This is the stuff that is used to seal double glazing units.


How about applying a bead of this around the perimeter of each cell onto the glass. Notice it cures by absorption of atmospheric moisture so any moisture between the cell and glass will be absorbed in the curing process.

Here is a link to the data of a product sold in UK.

http://www.kingfisheruk.com/specs/data/polysulphidesealantpds.pdf

It has very good U/V resistance and 20+ yrs service life. Oh and it

russ
01-31-2011, 10:48 AM
I asked the pu man to comment if he would - he may have some insight into the product.

RUss

Calgirl
01-31-2011, 10:49 AM
Have you ever worked with sylgard???? I have and it's a very thick substance.
I don't think you could coat them and hang them up to dry. and the wireing would be weakend also. Good luck to you if you can do that..Why don't you put the sylgard down then put the cells down then cover the rest with the rest of the sylgard. do this all at once. O Don't forget the backing.

You are quite correct that I have not built any panels, however, I have two panels, which have been soldered and are ready for encapsulation. I halted the panel building process when it became evident that my planned process to protect the cells and wiring was not adequate.

I will soon see if your suggestion that the Sylgard solution is too thick (heavy) to cover the cells by dipping, or that hanging the string to dry would destroy the soldered joints or harm the tabbing. I suppose that the quality of the soldering workmanship has a large impact, along with the weight hanging on the tabbing wire, and whether you manhandle the string. Your suggestion of laying the cells down on the encapsulant still has the problems with possible bubbles, but my guess is that it is better than pouring it on.

Since cost per watt is a consideration, the dipping process uses less encapsulant while completely covering the cells and wiring than hoping that the encapsulant seeps under the cells without any bubbles! If we can get more than one panel out of a given amount of encapsulant, then we are ahead. Since my three containers of Sylgard just arrived two days ago, I will soon have preliminary data. My expectation is that my proposed process will improve the longevity of the panels if it works, but of course, only time will tell.

Jeffc
01-31-2011, 01:42 PM
Sounds interesting, although a "bead" may not be enough to completely absorb moisture, etc. Since it is cheaper than Sylgard, it might be cost effective to pour or paint it on. If you give it a try, I'd be interested to read about your preliminary results.

Because it is applied with a mastic gun , I don't think it can be poured or painted on.
I plan to bead around each cell (using weights to press cell to glass, there should not be much air between.)I will seal 3 sides of each cell then use hairdryer to heat and expell moisture then seal fourth side.I will allow to set before I coat the rest of the cells.
If I do it all at once I run the risk of the sealant contaminating the front of the cell as the sealant is not clear.I think white would be best so as to absorb less heat.I will test first on some broken cells. Be aware that polysulphide can react badly with perspex and the like so glass is best.

JC.

Davidson
02-06-2011, 03:11 AM
This product would give far better UV stability over a standard Epoxy clear system agreed however if you check through the data it is a rigid system - a major no no. If you used this type of system during cycling it would crack and probably crack the cells as well. Any encapsulant used needs to have flexibility so that it can expand and contract without causing stress fracture.

I was thinking of Smoothon Clearflex 95, having 95A hardness.
put the solar string in a mold and fill the mold with this clearflex.
It's hardnees is not that high - so it will not crack.
It has no sticky finishing like the clearflex 50, so you don't have to put glass on it.
what do you think PU man?

solarrules
02-06-2011, 09:08 AM
I came across this forum while looking for a cheap way of encapsulating my panels.---Glad I did!

]

Check out this post where Rolland is trying to get enough DIYers together for a bulk purchase:

http://www.solarpaneltalk.com/showthread.php?3246-Slyguard-184-encapsulant-for-half-price.-Anyone-interested-in-a-bulk-order

It's roughly 1/2 the cost of Sylgard and perhaps better

the pu man
02-10-2011, 05:42 AM
Sorry All been out and about for the last few days. Ok looking through posts so far:

grayski41 - The use of the xylene I guess is simply so you can thin down on the viscosity of the silicone and make it go a little further. Nice idea but xylene is particularly nasty. I cant really see the benefit of using the xylene as it will potential eat into anything it touches bar glass. Has someone actually suggested you do this? I have never heard of using xylene on a two part system. Yes you can use it on a one part as essentially you are just adding it to thin it down - the xylene and moisture or other solvents evaporate to leave the cured silicone but 2 part systems do not cure like this!! The xylene may flash off but it would degrade the silicone. If it gets locked into the silicone 2 part then you would end up with a horrible mess.

Jeffc - Polysulphide Sealant is as you rightly suggested used for glass bonding. I think it was originally developed for windscreen bonding. They are a one part system and they absorb moisture in order to cure. I believe you could use it to cover the cell backs however suggest you check out the information prior to using problems I can see are:
1. 14 - 28 day cure - You would have to leave the panel open to the atmosphere for this period to get the required product
2. Minimum thickness of application is 6mm. Do you really have this sort of depth or are you actually looking at a coating thickness closer to 2 - 3 mm.
3. Refering back to use of differing materials you run the risk of a bond line failure between the encpasulation for the cells - clear silicone and encapsulation for the back polysulphide. I doubt you would get adhesion between the two. This would allow a direct water path between the two materials.

It could well be that this product could be used as an edge sealing system for the panel, just like you would use it in double glazing or windscreen appplications.

Just to give everyone an update we are now in the process of testing and evaluating one of our PU system. We are working with a company called Know your planet in the UK who are already set up to market parts for solar cell manufacture. It is going to be around 3 months until we launch the product to market as we have to run UV chamber tests on actual finished panels. We will try to keep everyone updated as we progress and we intend to post videos etc on the net. One of the major benefits we can already see, other than being in the region of half the price of the sylgard is the viscosity. It is currently like single cream in viscosity so it has massive flow benefits. One thing we are tyring to ensure is low toxicity. Most PU clear systems use a toxic ingredient on the Part A side. Please if anyone does try other PU systems watch out for the skull and crossbones symbol - believe this will be different in the US as they now have differing labeling to the rest of us. If you do see anything that says toxic by inhalation make sure you work with it in a well ventilated area. This goes for Grayski as well Xylene is not nice so stay safe.:amen:

Sorry missed you out Davidson - If I understand correctly you are going to pour in a coat of the product into a mould, let this cure, place the cells in position on the coat and then pour a second coat to totally encpasulate. Then you end up with a semi flexible mat of encpasulated cells? Are you going to put this into a glass housing or just then use it as a finished panel? I like this idea and its out of the box. Why do we need to focus on glass bonding and sealing when you could actually do this. The downsides for you are that using the 95 A the mat would be flexible and solar cells are extremely brittle and liable to crack with any flex of the mat, just a small amount of movement would run the risk of breaking the cells. I might try this one but actually use a rigid system. If you could produce a panel in this method producing a rigid encapsulated panel without glass you would significantly reduce the materials used and the problems of moisture absorbtion. You could even make panels which were shaped to a surface, why does a solar panel have to be flat? Time to contact the patent office I think!!

wayhopper
03-23-2011, 01:26 AM
Rolland, what is the status of the shipment? Is there an official shipping number yet?

wayhopper

longwolf
03-24-2011, 01:11 AM
Hi guys!
Wow, I come back to give an update and see that we've been stickied.
Kinda makes ya feel special, lol :julie:

I haven't been to the site in a while because of another project. I've done a waste oil conversion on my old diesel van and I'm happy to report that I've now driven about 100 miles running on WO :)
I'm still living in the van so the pre-filtering setup must be powered by the van. It uses a 500 watt, home made centrifuge. So i kinda need to make another panel or two soon.

Anyway, to recap, last July I built a solar panel using Clear Seal. It's made with 6' by 6' cells and is 58.5' by 27.25' and took about $24 worth of CS. It has 8 interlaced bypass diodes. I thinned the CS with mineral spirits and did the pour in two steps, which turned out to be a mistake. It caused several bubbles, some large, and I cracked a few cells while I was at it. Despite that, the panel tested out with 20.3 volts at 7.6 amps at noon on a summer day. After it had dried for a couple of months, I covered the back with Reynolds Wrap for added moisture protection.

So the panel has been riding on the top of the van since then. It's been through a Texas summer and winter and seen temperatures from 105 to -7 degrees. It's been through rain, freezing rain, sleet and several inches of snow. It's been driven over speed bumps, pot holes and at speeds up to 75 mph.
About 2 weeks ago I re-tested it. It was 1 PM, the panel was a little dusty and I wasn't quite able to angle it directly toward the sun. The reading came out at 20.21 volts and 7.64 amps.

So far so good :)

I'm also happy to report that the panel hasn't spontaneously combusted or suffered from the mineral spirits that were used.

grayski41
03-28-2011, 03:07 AM
the pu man - Thanks for your comments, thinning with xylene was recommended in an online book i downloaded, im no chemist so can only go on advice, is there maybe something else i can use to thin the 2 part silicon? it is alot easyier to use when thinned down, but i guess if there was the manufacture would have done it to bulk out ther product and sell more... I think from a diy point of view a thin coating on each side of the cell opposed to total encapsulation would make any future repairs easier. i know we all hope to not have to touch our panels again once on the roof, but its not likely.. BTW good luck with your project i recently purchased some bits from Know your Planet UK very nice people,, :p

Mike90250
03-28-2011, 02:45 PM
.....

So the panel has been riding on the top of the van since then. It's been through a Texas summer and winter and seen temperatures from 105 to -7 degrees. It's been through rain, freezing rain, sleet and several inches of snow. It's been driven over speed bumps, pot holes and at speeds up to 75 mph.
About 2 weeks ago I re-tested it. It was 1 PM, the panel was a little dusty and I wasn't quite able to angle it directly toward the sun. The reading came out at 20.21 volts and 7.64 amps.

So far so good :)

I'm also happy to report that the panel hasn't spontaneously combusted or suffered from the mineral spirits that were used.

Good News, thanks for the update

charlie_ruizpr
04-30-2011, 06:10 PM
Hey longwolf, How many ounces of liquid nails clear seal will I need for a 108 cell panel?

rollandelliott
05-01-2011, 11:18 PM
slygard 184 do is what everyone complains about becuase it is expensive and has air bubbles.

but there are 4 other solar encapsulants:
dow 6010 around $36/kg
Elastosil 2202 unknown price
EpicResins d9940 $7/kg
qsil 216 around $25/kg

just do a google search for solar encapsulants and you can get more info, the companies might even send you a free sample if you ask nicely.

the reason people do NOT use these encapsulants is some have minimum orders of over $1000.00

longwolf
05-08-2011, 01:19 PM
Hey longwolf, How many ounces of liquid nails clear seal will I need for a 108 cell panel?

That's hard to say. My panel was a little less than 1600 sq inches. It's been a while but I believe I used 7 of the small tubes that Walmarts sells. That was enough to glue the glass to the frame, make a dam around the cells then do the pours. I think the tubes were either 5.5 or 6.5 oz each.

longwolf
05-08-2011, 01:22 PM
slygard 184 do is what everyone complains about becuase it is expensive and has air bubbles.

but there are 4 other solar encapsulants:
dow 6010 around $36/kg
Elastosil 2202 unknown price
EpicResins d9940 $7/kg
qsil 216 around $25/kg

just do a google search for solar encapsulants and you can get more info, the companies might even send you a free sample if you ask nicely.

the reason people do NOT use these encapsulants is some have minimum orders of over $1000.00

Wow, those look like some good prices.
Do you know which will do small orders?
Will the EpicResins d9940 stay flexible?

Alan
05-12-2011, 08:59 PM
epic resin d9940 is pretty good just made a sample hockey puck sized piece for testing. you can bend it in your hands, but it is not rubbery/bouncy like silicone is, more like a semi hard plastic. got if off ebay.

Plinkomax
05-18-2011, 11:51 PM
Hey guys,

The amount of information on this forum has prompted me to register rather then lurk.

Any thoughts on DAP titanium silicone?

http://www.dap.com/docs/tech/00078670K.pdf

This seems to be similar to a platinum based silicone that someone was talking about earlier.

The important aspect is that it wont corrode metal.

My plan would be to cut it with paint thinner (mineral spirits) so it could be poured into the frame.

Mike90250
05-19-2011, 04:19 PM
Any thoughts on DAP titanium silicone?

From their data sheet

Discoloration may occur with copper and its alloys; try a test area before using.

Not recommended on surfaces that might bleed oils, plasticizers, or solvents. Best adhesion and
compatibility are not achieved with substrates made of methylmethacrylate, polycarbonate, polypropylene,

Not recommended for use underwater or below grade

It provides a long-lasting, flexible and watertight seal.


Watertight is not water vapor proof. I'd try it on a small part, abuse it, and then see what happens.

Plinkomax
05-20-2011, 12:18 AM
I had difficulty finding DAP titanium but it looks like GE Silicone 2 eaves troughs mix has similar properties.

The curing agent in this case is methanol and ammonia, which is nice because mineral spirits is ethanol and methanol based. Should reduce the toxic gas.

This could cause problems with plastic front covers but I will be testing some out this weekend.

Alan
05-20-2011, 10:54 PM
@ $6 per 10oz tube why bother? you can get "real" encapsulants for the same price NT

Plinkomax
05-20-2011, 11:51 PM
The silicone works out to about $21 per kg

Please point me in the right direction.

RJMcSherry
05-27-2011, 02:26 PM
epic resin d9940 is pretty good just made a sample hockey puck sized piece for testing. you can bend it in your hands, but it is not rubbery/bouncy like silicone is, more like a semi hard plastic. got if off ebay.

How easily was it to mix the D9940 by hand? Were there a lot of air bubbles trapped in the resin?

Has anyone used the D9940 on a panel and have had successful results?

Alan
05-29-2011, 02:41 PM
"The silicone works out to about $21 per kg

Please point me in the right direction. "


search ebay for solar encapsulant d9940 or if you want to spend more dow 6010 those are the cheapest two solutions.

the d9940 has bubbles in it, but they are much easier to get out than the sylgard. Will you have a panel with zero bubbles? probably not, .....Will it still work great, sure.

jeanlafete
08-19-2011, 03:16 AM
Has anyone ordered any of this encapsulant? The price is great, but the shipping is a killer unless a group went in together and ordered it.
Just looking around and found it....... Thanks

15 Liters comes out to about $50 a liter.

http://www.aliexpress.com/store/104108/210248460-359001497/liquid-silicone-for-solar-bond-encapsulating-material.html

Mike90250
08-19-2011, 10:28 AM
You need to find out what the cure method is. It appears to be 1 part, with moisture cure. Is it chemically neutral (acetone), which is safe to use on electrical parts, or is it an acetic acid cure ? (both are humidity activated).

RJMcSherry
08-30-2011, 12:33 PM
*EpicResins D9940*
http://www.epicresins.com/solarPower-Bonding.asp
http://view.vcab.com/?vcabid=eaaSppgnScprlle&count=29/04/2011%2016:05:59-2

*DOW6100*
http://www.dowcorning.com/applications/search/default.aspx?R=8095EN

*DOW6010*
http://www.dowcorning.com/applications/search/default.aspx?R=6245EN

*Sylgard 184*
http://www.dowcorning.com/applications/search/default.aspx?R=131EN

*Solar-Tite 384*
Have yet to find the actual datasheet for this product, but there a lot of reviews for this floating around the internet and it is readily available from ebay

*Elastosil 2202*
http://www.wacker.com/cms/en/products-markets/products/product.jsp?product=11344

*Cell Guard*
Once again, can't find a data sheet for this. But it is a product of ML SOLAR and can be found on ebay

*QSil 216*
http://www.quantumsilicones.com/PDFs/data/QSil%20216%20Data%20Sheet.pdf

*OptiTec 7020*
http://www.intertronics.co.uk/products/opt7020.htm

*GE RTV 615*
http://www.dcproducts.com.au/RTV_Silicone_Solutions/Tech_Data_Sheets/RTV615-tds.pdf

jimbo100
10-10-2011, 10:24 AM
This thread has been a great help! I am a new member here and this site is just what I have been looking for. I have just recently purchased 1KW of 6X6 .5V 8AMP + cells and am in the process of building my panels. I will try to document my progress to post here! Thank you very much for your help.

Thanks
jimbo100

superduperenergydude
10-11-2011, 09:24 AM
do yourself a favor and return the cells or resell them.
you can buy panels without the frame for 59 cents a watt it will cost you over $1 per watt for just the materials with labor probably over $1.50 a watt.