Harold
" No surprises with those 6 X 6 cells ?? I was going to have my son pick up some tyvek, when I talk with him, tonight. Might just skip that and buy plastic on a roll at the local hardware."
Yes!..... Do not pull a full vacuum on these biggies at room temp. They will crack along the tabbing wires..... without exception almost.
I found that if you preheat to 50C, and then start the vacuum process, that all the cells survive perfectly, and the output reflects this. This is also good advice for the 6x3, which seem much more robust, but stll the occasional one broke along the tab if I did it at night and the temp was cool.... so preheating is a must I think for all cells now.
I prefer the plastic to the tyvek. It makes for a very clean an neat backing.... also if you push the temps up too high with the tyvek, it will dissolve into a not so pretty backing.... no detraction from the usefulness, but I find it nicer to use the plastic sheet...... Also, if you get a broken cell it is simple to fix if you can see all the wiring in the back of the cell crystal clear..... a cell bypass is simple then.
Howlet, I tracked down your picture of your panel. It looks the bees knees. How has it weathered... very well I trust..
(hope this is it):
![Making decent solar panels part 3](https://www.fieldlines.com/index.php?action=dlattach;topic=145004.0;attach=2527;image)
Did you do a story on it someplace?
From the cracks on the second from left top cell, I suspect that the vacuum was pulled on before any temp had gotten into the EVA (but you probably know that by now anyway)..... but the drift exhibited tells me that the broken bit drifted when the EVA went liquid..... as if the backing was not stable? (ie what did you use for the wicking... did it move?)
The big bubbles worry me a bit. Did you hold the pre 65C vacuum on for too short a time?... or is there some other explanation I should know about. I have not seen this in any of my cells (please share any bad experiences and the "fixes" for them for mine and other folks benefit..... your years in front of me)
I note your disappointment with the reception that most DIY solar efforts receive..... and mostly for good reasons. If yours are EVA laminates, vacuumed (need the pressure too) and without bubbles....... gee it's hard to see how they could possibly fail (unless someone puts a brick through them). They are sealed up but good..... for good, and providing you use decent EVA and cure it well , it should not denature.... it is designed for it, and better than the older generation of the stuff..... and the old stuff was pretty serviceable as well.
I suspect that those that deride DIY panels, have taken the wrong path themselves, and or seen others efforts end in tears.... so their skepticism is probably well placed.
In my case, I am isolated, so transport is a difficult thing for delicate big things, and old solar water panels are plentiful here (about the only thing that is). I know how tough the EVA end product becomes, and am very confident in the aging being little different to the commercial panels. In truth, it will be the panel to panel connecting system that will be likely to require the most effort from here.
Those using heat guns will get a reasonable short term result, but they have only melted it.... not cured it and it will likely lift off the glass eventually.........,unless they got it very hot... uniformly, then it just might stick forever.
If it's not mostly/fully cured under pressure (temp and time tests), it may not bond to the glass long term. If they don't get the glass clean... ditto ( at least the cells will last inside the EVA envelope, but may break if they leave the glass,) or get moisture in front of them. It is not fool proof by any means if done poorly (but nor is anything else)
So even EVA enveloped cells can still come in for some well directed flack.
Good looking work Howlet
.............oztules