[88726]

hi guys

started building my solar panels , im finding the soldering very difficult and i have years of experience in soldering, i was warned about this beforehand , does anybody know where i can buy conductive adhesive (apoxy)at a decent price , maplins want 22 quid for a small tube but it must be cheaper somewhere else .
cheers
kenny+stella

 

[spykal]

Hi Kenny

I have never tried to solder photo cells and as you say that you are experienced I am a little hesitant to offer advice but here goes anyway...is the soldering iron you are using big enough...it may take a lot of heat to get the solder running well, a small capacity iron may not do the job.

Have you tried different fluxes and pure solder instead of the cored type. Modern solders are usually lead free now and do not solder as well as the old lead solder. Try to get hold of some old lead solder and try Bakers Soldering Fluid No 3 as the flux. Bakers is known to be corrosive so if it works you will have to clean up the joint carefully after soldering.

Sorry if you know all this already but I was following your threads on the building of solar cells since I fancy a go at it myself.

Mike

 

[88726]

hi mike

the problem with the cells is the pads are a silver that is fired on to the silicone directly by specialist process , so its not really a pad its more like a picture of one if you know what i mean! its only a few microns thick and the thickness is varying , i am using a silver solder to reduce the leaching of the fired silver into the solder and a quality heat varying solder station and have tried 3 fluxes one especially for silver but its still hit or miss , theres about a 2 second heat window before the pads gone , ive done 108 joints in total but about 30 gave up , theres 6 joints per cell and its usually just one of the 6 that goes awol , if it goes wrong first time the second chance is very very slim , im happy to leave the good joints alone and bond the bad ones with conductive epoxy to finish the panel but its very expensive stuff from maplins i need a reasonabally priced source.

i cant think of any other way to attach solder to silicone unless theres a specialist acid or my alternative which is conductive epoxy.

all advice apreciated .
cheers
kenny+stella

 

[spykal]

Hi Kenny

I now understand why you thought of using a conductive epoxy!, and I was right in thinking that you had possibly explored all the avenues when it came to the actual soldering.

Thats a real pain in the Butt after all money spent and the work you have done on getting the right components. I do hope you manage to get an answer to the problem. I think I will put the self build solar panel on "Hold" for a while :lol:

Mike

 

[88726]

hi mike
dont give up the idea as i think its a worth while project despite the probs , cost is a bit steep now but im still saving . if i could only find stuff at the price the manufacturers do . think i will finnish the 1st panel and shelve the rest for now as its too time consuming at the moment .
cheers
kenny+stella

 

[88726]

hi guys

ive finally got all the cells connected and tacked to the base , will try it out and post some pics when i return after the weekend.
cheers
kenny+stella

 

[88726]

hi guys
panel now built , next to fit it to the mh and wire up the charge controller , tried it out today in the sun at 2pm and its pushing 19.5 volts , shaded it about 1/3 and the voltage dosn't drop still 19.5 v , heres the pics as promised

 

[88726]

the prepered baseboard .

 

[88726]

soldering the arrays ,

 

[88726]

panel built .

 

[88726]

panel glazed and ready to fit

 

[88726]

oops!

cant see my pics ? not sure why . theyre in my album if you want to see them.


any ideas why the pics didnt appear in the posts ???????????????????

 

[88726]

anyone ????????????

 

[johnsandywhite]

Yes theflyingscot they are in your album. Was it worth all the hassle?

 

[88726]

hi johnsandywhite

yep i know theyre in my album i actually wanted the pics on the thread postings but cant figure out why it hasn't worked this time as ive posted pics before .

i did enjoy building them and i think it was worth the hassle as it was loads cheeper and now ive done it it would be easier second time round . i always like to see if i can make stuff for myself and i usually end up learning loads as i go . suppose its a sort of hobby :lol: :lol:

cheers
kenny=stella

 

[johnsandywhite]

That's the only way to learn. Do it yourself. What is the final cost for the completed panel?

 

[88726]

hi johnsandy

comes in about £82 for a 60 watt panel but i had to fibreglass my baseboard as it was too flexi ,

if you could find a sheet of fibreglass for the baseboard ( maybe from a breakers yard ) van roof old boat or something you could probabaly do it for about £70.

cheers
kenny+stella

 

[johnsandywhite]

I don't want to rain on your parade. But you can buy them for that price on ebay. :?

 

[spykal]

Hi kenny

Well done for sticking at it, you must be well pleased with it.

A thought about the base board, I once made a very strong base board for a model by sandwiching a one inch thick polystrene foam centre between two quarter inch thick pieces of plywood. the plywood was glued to the polystrene with water based latex adhesive (like copydex). This made a really strong and light board which was torsionally strong due to the "girder" effect of the two skins of ply separated by the polystyrene. I got the idea from making model aircraft wings, these have a foam core with a thin wood veneer covering. A bit late now to come up with a suggestion I know but I bet you will be having another go now that you have "cracked" it :lol:

How do the manufactured ones stiffen the bases?

Mike

 

[spykal]

I don't want to rainon your parade. But you can buy them for that price on ebay. :?

I have not seen any good 60 watt panels for sale on Ebay for that sort of money, let me know when you see one. :lol:

Mike