kWeld - "Next level" DIY battery spot welder

Battery is new.

Did calibrate the system.

At least I can't see any faulty connection.

What about the material on the tips and the sparks? I assume this is user error?
Tips shouldn't be sparking to much if you aren't using nickel plated metal. Then it will spark a lot.

You can try cleaning with alcohol. It will remove the non-conducting oil as well as smoke (coal / carbon) that will populate the tips after a while.

What thickness are you using and what power levels? I think I only used 100J around for 0,3mm pure nickel and for 0,2 50J-->80J but to my knowledge after experience even those power levels I used was way too high!

So pulling down the power to when the nickel fastens correctly is something you need to learn and go from there.

I don't think "ONE" lipo can do 1200 amps+... but I may be wrong so in a sense that may be an easy answer to a tricky problem here.

Is the kweld newly build? I have had a ONE nut lose on it on the copper bar row and it acted weird. Also ONE time it has been a little lose on the positive or negative INPUT or if it was OUTPUT. It is sure worth a double check here. Be careful not to short or drop metal into the kweld, allthough mine survived a short once I don't expect luck to be on my side always.
 
hi, new to kweld.
recently salvaged 21700 tesla model 3 cells. their positive side is aluminium and challenging to spotwelding.

any confirmation kweld can spot weld positive side on those cells? no puncturing? read some claim it can be spotwelded with kweld immediately after sanding positive side before oxidation happens again.

what setup? jowls?

what setup for negative side spotwelding? (welding at bottom?)

thanks
 
Can anyone recommend what is the best series configuration for kweld? I'd like to have 2S (for higher parallel set) since their website lists the kweld from 4 to 30V. I see most recommended batteries listed as 3S - is there any downside of using 2S?
 
I don't think the KWeld is meant to be powered by a 36v battery. I use a bank of 12v batteries for mine.
 
I don't think the KWeld is meant to be powered by a 36v battery. I use a bank of 12v batteries for mine.
The pack is 12S 8P. There are screw terminals for each parallel group which allow it to be reconfigured from 1S to 12S.

4S will give 14.4 V
 
So 4S/24P? That's something like 1,200 plus amps at the cells 50a current rating. One would think that will work!
 
So 4S/24P? That's something like 1,200 plus amps at the cells 50a current rating. One would think that will work!
4S 8P is easy, just tap off a screw terminal. 4S 24P will need cutting it into 3 sections and wiring them in parallel.
 
8P would be something like 20ah. I wonder what power the KWeld draws per weld, at some average value?
It's your experiment, sounds like you got it figured out.
 
I tried a 4s lifepo4, i got an overcurrent problem I think (warning in the welder). I wasnt able to run it anyway, and just went with a 12v car battery.
Can you post the specs of the 4s lifepo4 you used?

edit: This was helpfull on power options for Kweld How to choose a suitable power source for kWeld Spot Welder

I have a H8 (group 49) 900 CCA battery in my car that I could use. One negative is I have to remove it from the car so it can be used on the bench. It's a heavy battery!
 
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not yet, but we are making a first batch of 20 right now. I hope to be able to open up for preorders before Christmas. The first units will be kits, and I might have a price point in one or two weeks from now. Software will be limited when they get released, but we are and will remain working heavily on that thereafter. My plan is to reach at least kWeld status, with proper energy metering and of course capacitor voltage control.

And to your question: it has already done stress testing with full steam 13ms / 3300 ampere pulses, once every two seconds. Sock solid after 100,000 cycles :) That amount of current is definitely by far enough for 0.3mm nickel, and also solid copper sheets should be possible. But I havent been able to test many variants yet, rather concenrating on development. I'm curious to read what you guys will achieve with it.
Hi Frank, almost a year later, we are waiting for some updates. when can we purchase the Kweld Pro?
 
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