Copper to S.S.

[Little Motor]

If I were to silver solder copper to stainless steel,
would I get electrolysis at the connection point?

[Bob]

You would get some reaction between the disimilar metals no doubt like welding cast iron to steel
they react against each other and eventually will fail.
 However, lets say you took 2-4" square plates one copper and one stainless steel and soldered them togeather very well... ( with no pockets of missing solder in between them, an almost impossable task!)
 what would the electrical path be if you used that as a single plate?
sense stainless steel is a rather poor conductor and copper is a very good conductor almost all of the electrons will flow to the copper and not the stainless steel thuss it would be like using copper plates
in a hydroxy cell and it would GOO up in a hart beat... making it unusable.
however if you sandwitched a copper plate between 2 sheets of stainless steel you may well get the benifit of having High conductivity and stainless steels resistance to crosion. as only the edges would be seen and that could be covered by the silver solder... which is fairly clean in itself
...
but the question is what are the benifits of good conducting plates ?
 mainly more power gets to the right place and is not lost due to resistance.
 so 10 amps would get to do 10amps worth of making gas for you... and no heat except from minor resistance in the sandwiched plates.
  This all sounds good except that Stainless steel isn't that resistive to electrical flow in reality
unless you are running 3ft square plates I doubt the results would be worth the hassel.
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I THINK such a cell would run cooler, but that remains to be seen actually, and the inherent Goo production of the copper may well make the idea useless in and of itself.
with copper in the cell there will always be some goo production... unless you seal it up so well that electrolyte cannot get to it.
...
 Keeping resistance to a minimum is very important there is no doubt about that... but there are such things as going OVERBOARD with the idea too ! HAHAHAHAHA
....
would it be worth it .... I seriously doubt it !
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A fella named "SCRATCH" made 12"x12" plate cells and theorized that if he fed the large plates at 2 places on each plate(opposite corners) that it would work better ... and I think he tried it and it did indeed help, the production was increased a small amount. so yes on larger things plate resistance starts to play a bigger part , however on small cells one feed point is usually enough!
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as far as electrolysis on different metal types  joined together , that is a Very old and known problem and it occurs on any metals, you can be sure of that.
 the deteriation of the metal occurs because of the different work-force in the electrons of the 2 metals.... attaching 2 metals together such as steel and silver will cause this reaction even if their just bolted together... contact makes it happen... if you are using an electrical system on the parts such as a generator to run an engine and charge the battery the deteriation will be accelerated dramatically, because the flow of electrons is increased.
 On marine engines and Hulls they usually install a Zinc Anode block as a sacrificial hunk of metal to direct the electrolysis to the Zinc and not the rest of the hull.
 when I was a Kid my Dad made a big Inboard boat and we used it to go skiing behind allot, one day we pulled the shaft log out of the boat to have it straightened (we hit a log!) and discovered that electrolysis had almost eaten the bronze drive shaft in half!.... we added a Zinc anode at the rear of the boat and ran ground wires to it and that cured the problem.
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Electrolysis comes in a few different flavors, the type in Boats and the type in generators being used to make Hydroxy gas....  there may be more types, but I don't know what they might be!
hehehehhe
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 so to make a long story short.... (tooo late I know!)
... YES
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FWIW
Bob....

[Little Motor]

Thanks Bob, I was thinking of silver soldering the power supply (copper) to the
stainless plate. The join was not going to be submerged. But then again I might
submerge the join if I thought the connection would last.
Thanks

[Bob]

it should last for a while but the problem is the goo you would get if you did it that way.
its not worth the GOO believe me !  the copper will leach bunches of green goo into the electrolyte and
slowly render the cell inoperative because the goo coats the plates....not good
the only thing that I found that will clean the cell then, that I have found, is a Muratic acid bath to loosen the goo and then high pressure water-hose to blast it off...
(I used 100% Muratic acid for ten minutes, then dump and flush. this is very hard on insilators!)
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Copper should NOT be in the cell with the plates... period. weather its under the electrolyte or not
because of this problem. its far better to use stainless steel as tangs to attach to. or stainless steel strips as electrical connections.
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 Ususally when connecting plates in parallel guys just cut notches out of every other plate to get by the other plates and still make the connection with the correct plates needed...this works very well.
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However when running a bunch of neutral plates this type of hookup is not needed infact I am sure thats why they came up with it , its far easier! just use a Stainless steel strip to the plates on the end and your done!
...
Bob......

[Little Motor]

Thanks again Bob. I'll forget about the submerging, not a good idea all.
My original thought was to connect the plates with copper outside the chamber,
no copper at all in the chamber.
The area where the connections occur would be encapsulated in a block of rubber outside
the chamber.
So my concern is because of the encapsulation I would not be able to observe the connections,
would there be some sort of electrolysis going on between the dissimilar metals?

[Bob]

of corse... anytime you connect two diferent types of metal you will get some kind of crossion and it will be very hard to keep the connection electrically GOOD ! this is why bolts are usually used to connect battery clamps  even though they are made of the same metal type a JOINT is where corrosion will build up.... its a point of resistance, resistance means heat and heat causes a speed up in corrosion.... or electrolysis... what ever you want to call it...
its that JOINT that you want to avoid if you can....
 I saw a Cell pic of a guy that had hard wired something like 30 plates with No#10 copper electrical wire.... it was a work of art, but....can you amagon how hard it wouldbe to keep all those connections making good contact ALL the time ?
 there is a grease that you can put on the connecting joints that virtually eliminates the effects of corrosion/electrolysis ... its an electrical contact grease, and you can usually pick it up at any electrical store... using this grease on the connections will keep the connections alive longer...but not forever.   but if you figure you will have to tear down the cell in a year or so to clean/rebuild it, at that time you could re apply the electrical grease and you should be good to go !
... so instead of silver soldering the joint bolt them together with lots of the electrical grease and then cover the entire thing in silicone (clear stuff) as long as the joint stays tight you should be in great shape, so using lock washers on it would help.... use SS bolt and washers and lock washers
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 Most cells ,(mine included) exit the cell with a stainless steel threaded rod that is sealed to the container water tight with High temp silicone sealant and a crushed piece of gas line between 2 ss nuts.    this is a wet cell design, obviously not a Dry cell where the contact points are exposed to the outside world by default.
From that point (Outside the Cell itself) just running Heavy copper wire will do the trick.
depending on the amps used you need larger wire obviously... (more amps = bigger wiring)
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 but as far as attaching a electrical connecting point to a Plate ...say like a stainless steel strip 1" wide 6" long to reach outside the cell for power,.... silver soldering or welding is a very good idea... as that type of connection will probably out last you !
but if you mix the metals and run a copper strip to the plate in the same manor it will probably fail in a year or two because of electrolysis or corrosion.... and besides you want to keep Copper out of the cell so using all stainless steel seams like the best way to go.
......
 I am planning one day to make a 60 plate cell with all but 2 of the plates neutral plates....
which means the end plates will be fed with connections from the outside... these connections are very important to consider, because if the connection fails the cell stops working.
there is many ways to accomplish a connection to a plate but the most common is bolting which had doubious results because of the apt to be loose connection. heat and expansion and contraction will make it almost impossable to keep in good contact... so welding is usually perfured over bolting
(without mixing metal types) i.e. weld a stainless steel bolt to a stainless steel plate with stainless steel welding rod. and that if done correctly will last a life time.
... so I plan to weld the tangs on to the end plates on my 60 plate cell... (if I can ever get to the point I can order my plates ! LOL)
 at present I am contemplating different wiring than the straight series described above as I think
I can make better production by feeding both ends with the positive lead and the center of the cell with the negative lead... but I am not sure what that will do to my voltage per plate setup...
and if and when I do this I want to do it right so I can get at least 15to 20LPM from the cell at 120vdc and about 30 or 40amps.
I should be able to accomplish this as others have with large series cells (Bob Boyce included, its his design after all!)
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many things need to be considered when desiging a cell from scratch, its easier by far to make a cell that someone else has already figured out how to make it work good !
the Dry cell or the Randy cell are very good cells as is the Smack booster (if you can find the parts)
....although the Series cell of Bob Boyce is not for the faint of hart it is a very proven design
powering it however, is another ball of wax all in its own!<GRIN>
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Hope that helps !
Bob......