Battery Spot Welder

[LewTwo]

Question 1:
Are any of the inexpensive (dare I say cheap) battery spot welders on EBAY worthwhile?

Question 2:
Does anyone make a battery spot welder that can be powered via a 36 or 48 volt ebike battery rather than 12 volt automotive battery?

Thank thee

 

[john61ct]

#2 is definitely the tail wagging the dog.

Everyone says No to #1

get the one discussed in the very long thread here, that is the cheapest one that has a chance of working.

And don't skimp on the battery, buy the reco voltage, higher Ah capacity than you think you need, and top quality if you want it to last, new cells not secondhand.

Even then it's a challenge, so mind your Ps & Qs to increase the odds of good results.

 

[LewTwo]

#2 is definitely the tail wagging the dog.

Well I do not have a car so no automotive battery that could be used without wasting money on something that would not otherwise be used. I do have several E-Bike batteries including a LiFePO4 rated for 25/50 Amps @58 volts. It was a question worth asking.

Everyone says No to #1

kind of suspected that

Might get a Sunkko 709A for the project and then sale it used at a loss. Thank thee.

EDIT ... for the record:
After much cruising the internet I found a Youtube video where someone compares all the approx $20 12 volt DC PCB spot welders that he could get his hands on. The winner was one labeled "BIFRC". Note that the the PCB is $20-30 from China and you need a few other things:
1) Probes and cable (16mm2 or 6 AWG) ... the good ones run about $35
2) Battery with 7-16.8V power supply with capability of 150A or more instantaneous output. The cheapest Lipo that meets thhose requirements is $21 but only 1500mWh. Realistically figure about $65 ... plus charger, ballancer, power supply ....
So the 'cheap' $20 spot welder is really going to cost one about $100

https://youtu.be/oIDYV20cKrM

 

[john61ct]

YT is a terrible primary source for getting any category of information when you are first starting out to educate yourself.

 

[LewTwo]

YT is a terrible primary source for getting any category of information when you are first starting out to educate yourself.

YouTube is a bit like political speeches: one needs an adequate BS filter in place :wink: