Spot Welding using modest current. Ideal for making up Battery Packs?

dunnyrail

dunnyrail

DOGS, Garden Railways, Steam Trains, Jive Dancing,
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#1
Just found these two Vids. Seams an interesting concept, I just wonder about the tech but appears to work. Though in the second vid he only appears to be Welding Silver Paper together, however this may be of use in Coach Lighting. Would appear to be what they do to the internal wiring of some makes Points (certainly some LGB and Peco) though I imagine more Power would be needed in those instances.

Vid 1


Vid 2

 
G-force1

G-force1

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#2
My C. turkey will get thicker foil than that! Perhaps I'm not thinking out of the box enough but I can't envisage needing to stick foil together like that and it did blow quite a few holes. Interesting none-the-less! The battery packs were nearer the mark.
 
Rhinochugger

Rhinochugger

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#3
Toooooooooooooooo risky - I'll leave the battery packs to others.

Otherwise, I'm happy with my soldering iron :rock::rock::rock:
 
Greg Elmassian

Greg Elmassian

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#4
Both of these guys are doing this the wrong way... they are not passing the current through the 2 pieces to be welded, thus FORCING and ENSURING the weld to be at the interface between the 2 pieces, but they are doing the current transfer on the SAME piece of metal, and the molten spots on the top piece are enough to melt SOME metal to the piece below.

Funny how they did not understand this, with a simple change in placement of one "electrode" you would get much better welds.

Greg
 
dunnyrail

dunnyrail

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#5
Both of these guys are doing this the wrong way... they are not passing the current through the 2 pieces to be welded, thus FORCING and ENSURING the weld to be at the interface between the 2 pieces, but they are doing the current transfer on the SAME piece of metal, and the molten spots on the top piece are enough to melt SOME metal to the piece below.

Funny how they did not understand this, with a simple change in placement of one "electrode" you would get much better welds.

Greg
Interesting, was looking for comments but not sure how your suggestiin would work with Batteries Greg?
 
PhilP

PhilP

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#6
You move one electrode to the metal of the battery terminal itself.. Then the current has to flow BETWEEN the two materials..

However, not really enough 'oomph' to do the job properly, and the connecting strip looks a little light (in gauge)??
 
P

Paul M

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#7
Seems a good idea, but to do the job properly you're going to need a bit more oomph. If it could be made towork on etched kits, that'll be great, no messing around with different solders
 
G-force1

G-force1

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#9
You move one electrode to the metal of the battery terminal itself.. Then the current has to flow BETWEEN the two materials..

However, not really enough 'oomph' to do the job properly, and the connecting strip looks a little light (in gauge)??
There is plenty of president for both electrodes on the top (or bottom), the biggest problem is making sure that both plates are touching under both electrodes. Spot-welders were supplied like that (or with attachments) for hard to reach places on motor vehicles.
 
GAP

GAP

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#10
Interesting that in vid 2 he is using a 25V working voltage capacitor in a 27V environment.
Personally I would use a 35 or 50V, maybe even 63V to push it to the extreme.

Vid 1 is how I would do it if I ever ventured into that space (I just buy tagged cells and solder them)
 
PhilP

PhilP

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#11
one of the videos has a 12v motorcycle battery, plenty of oomph
:):devil::devil::devil::)

Also, the potential (or should that be capacity?) to go horribly wrong.

Think we need a 'Don't try this at home, folks!'

The old adage:
"It's the volts, that jolts, but the current, that kills!"
Still holds true.
 
Greg Elmassian

Greg Elmassian

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#12
yep, I agree, the "pressure" part is not well handled...

you can look for "mini spot welder" and find them inexpensively on amazon. Many people use this technique on brass locos to attach detail parts.

Also, for track power, spot welding jumpers between sections is absolutely the least expensive way to go for continuity, and done correctly is better than rail clamps.

Greg