dry cell project

[shamndi]

hello to all
this is my first post here,but i've been searching around forum for some time now.
my idea of building some kind of hho generator for use in the car is not so new, but since lately i haven't really started doing anything about it.
now i am building a dry cell. i got ss 316L plates from local vendor.plates are not in perfect condition (a lot of scratches,greasy...) so it will take some surface work to make them proper. cell will be 13 plate -nnnnn+nnnnn-. power plates are 160x120mm 2,5mm thick (little to thick i suppose,but want good current conduction over surface). neutrals are same size with one edge 25x25mm cut off and 1mm thick. gaskets are 2mm NBR. 2 outside plates will be 10mm thick plastic (not sure exactly what kind) sized 180x140mm to have 10mm space for 14 6mm holes for screws.
this is what i have constructed so far. now i need to make holes for liquid equalization and gas vent, get some fittings for hoses, water tank and probably a separate bubler with flashback valve (mouse ball type). water tank will also be used as the first bubler. maybe some additional flashback arrestor will be after the second bubler.
i intend to use it in my 1.8L toyota celica, so i am aming for cca. 1LPM at around 20 amps, which will be controlled with PWM (zero fuel type)
will post any update as project proceeds.

any comments and suggestions are more than welcome

[shamndi]

i am thinking of making 4mm holes on bottom corner (alternating left and right) for liquid level and 10mm holes on top for gas. i am not sure if one 10mm hole is enough or should i make 2,3?

[BioFarmer93]

Shamdi,
It sounds as if you are off to a good start. Your plastic end plates are a bit too thin though, at 10mm (.393") to torque down well without flexing away from the gasket along its inner perimeter. See if perhaps you can find some that is a bit thicker, or make two steel 6mm thick X 25mm wide reinforcing rings (rectangles) that are drilled for your bolt pattern to run around the perimeter or your unit. They will do much to equalize the clamping forces of your bolts and distribute the pressure over the entire surface of your gaskets.
Several members here have done that now and report great success.
I think (if it were mine) that I would use at least a 6mm hole staggered on the bottoms, and two 6mm holes at the top 40mm apart. Don't forget to media blast and use Weldon-16 in and around all of the holes.
Send us some phots as soon as you can!

[shamndi]

BioFarmer, thank you for your advices.
I'll probably need more as i proceed.
those 10mm plates seem too thin to me too.it is just what i had at hand.will consider getting some thicker ones or reinforcing those as you suggested.
if i make two holes on top, should i also make two gas outlets for hose fittings?
not sure yet about mediablasting.was thinking to use sandpaper for surface. Weld-on 16 is probably used for insulating holes to minimize current leaking. do you think that any other acrilic cement would do,as i don't think weld-on is available in europe?

[Darrell]

If you are not going to media blast the plates then Weld-on 16 will not to stick by itself. I have used ABS glue but you must heat it so it becomes hard when it cools and so that it will stand up to the elite. (Reminds me of a hard rubber grommit when complete). You must first fill the holes in with the glue then sand flat and redrill the holes. I then apply a glaze of weld-on 16 when complete. Weld-on 16 can be bought on ebay.

The end product seems to work quite well if applied correctly.

[BioFarmer93]

BioFarmer, thank you for your advices.
I'll probably need more as i proceed.
those 10mm plates seem too thin to me too.it is just what i had at hand.will consider getting some thicker ones or reinforcing those as you suggested.
if i make two holes on top, should i also make two gas outlets for hose fittings?
not sure yet about mediablasting.was thinking to use sandpaper for surface. Weld-on 16 is probably used for insulating holes to minimize current leaking. do you think that any other acrilic cement would do,as i don't think weld-on is available in europe?

Shamndi,
"Not sure yet about media blasting. Was thinking to use sandpaper for surface."
If at all possible, try to get them blasted, the improvement in gas production over sanding is very noticeable.

"If i make two holes on top, should i also make two gas outlets for hose fittings?"
No, it's not necessary to put two outlet holes on one side to match the holes on the plates, but your reactor will "breath" better if you center an outlet hole on each end plate between the holes on the stainless steel plates.

"Weld-on 16 is probably used for insulating holes to minimize current leaking. do you think that any other acrilic cement would do,as i don't think weld-on is available in europe?"
Exactly right, and I am positive that there is a European equivalent to Weldon-16, it is called Acrifix 116 from Evonik. But remember! If you do not media blast in and around the holes, the Acrifix will not stick to the stainless steel and will end up in your bubbler... (Plexiglas-shop.com (http://Plexiglas-shop.com))

Remember- photos!!:D:D

[shamndi]

power,neutral,end plate and gasket
power plate has 4mm hole for power connection
assembled stack is missing 1 neutral and two gaskets
last photo shows where i should drill holes all 6mm, if i understood correctly

[BioFarmer93]

Shamndi,
Looks good so far- don't forget to use some kind of rubber/plastic tubing around those bolts to keep them from shorting out your plates. Also, you might want to move that equalizer hole down to the edge of the gasket in the same manner that you have your gas vent holes at the top. Keep it up!

[shamndi]

Done drilling holes as BioFarmer suggested.
Will definately put some spacers,tubes for screws for insulation and for keeping plates and gaskets in place. Anyways i don't have right screws yet. Those are just for getting a feeling of how it will look, to get the right size of screws etc.
BioFarmer thanks for mentoring. It is good knowing that i am on right track.
Will keep posting updates.

[mattsimis]

Hi Guys, Im in Europe too and a few weeks behind the OP. Will be following a similar course. One question that still bugging me, this Weld-on 16 talk.. I have read many threads here and Im clearly missing something fundamental about it! Why drill holes only to fill them with acrylic glue!?

[mattsimis]

Ok found the answer to my own question. ;)
http://www.youtube.com/watch?v=XBp9QQ0eEoY&feature=mfu_in_order&list=UL

Weldon 16 isnt a "glue" at all.

[shamndi]

after some time i continue my work on a dry cell project
so far it is mounted on board for tests
i ran it on 2,5 amps using 4% KOH solution. will probably have to increase it to 30%-40% so that i can run my PWM for 20A constant current
for bubler i use water filter housing with hommemade mouse ball pressure relief valve.

[reggaerican]

One question that still bugging me, this Weld-on 16 talk.. I have read many threads here and Im clearly missing something fundamental about it! Why drill holes only to fill them with acrylic glue!?

yes someone please explain this more clearly to me... im sure your not filling in the whole that just wouldnt make sence to me so what then?? mattsimus posted a link to youtube but it was removed.

Someone preaty please help with this

[shamndi]

yes someone please explain this more clearly to me... im sure your not filling in the whole that just wouldnt make sence to me so what then?? mattsimus posted a link to youtube but it was removed.

Someone preaty please help with this

you dont fill holes, just around them. weldon is used to isolate holes and area around them, so that the least current passes directly through electrolite
see attached picture. plates are not mine and my drawing skills are not too good.

[shamndi]

you dont fill holes, just around them. weldon is used to isolate holes and area around them, so that the least current passes directly through electrolite
see attached picture. plates are not mine and my drawing skills are not too good.

and picture

[D.O.G]

Quote:
Originally Posted by reggaerican View Post
yes someone please explain this more clearly to me... im sure your not filling in the whole that just wouldnt make sence to me so what then?? mattsimus posted a link to youtube but it was removed.

Someone preaty please help with this


you dont fill holes, just around them. weldon is used to isolate holes and area around them, so that the least current passes directly through electrolite
see attached picture. plates are not mine and my drawing skills are not too good.

Weldon-16 is used to cover the edges of the holes to eliminate the "edge effect".

Have a read of this article, about halfway down the page, for an explanation of the edge and tip effect in electrochemical cells.
http://electrochem.cwru.edu/encycl/art-d03-curr-distr.htm

[Darrell]

Maybe this will help. "D"
http://www.youtube.com/watch?v=4eLsNvPtxX8

[reggaerican]

and picture
thank you so much for this pic I am forever greatfull and now one step closer to my first build.
likewise to you Darrell for the vid.
and im not forgeting you DOG that is some good reading for a later day explaining in detail cause and effect.. this place is great and I think im beggining to love you guys...:D