kWeld - "Next level" DIY battery spot welder
Re: kWeld - "Next level" DIY battery spot welder
My Sunkko is long gone. Was gone soon after the Kweld arrived.
- Compoundbike 10 W
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Re: kWeld - "Next level" DIY battery spot welder
ossivirt wrote: ↑May 26 2019 4:06pm
How to best describe the difference
I did multiple welds to 0.15mm nickel with sunko and prayed afterwards that even one of then would hold. With kweld every single one is constantly strong and I need pliers to rip off the nickel and it tears of around the weld points leaving the welds and rest of the nickel still attached to the cell.
I have the cheapest possible sunko welder so I had it at maximum settings and kweld beats it even at very low energy levels. (10j)
just ordered one.. cant risk disconnected batteries.


Re: kWeld - "Next level" DIY battery spot welder
Ossivirt ...so 50j and you got good welds for .1MM nickle plated copper? With the regular electrodes? I now have some .15mm nickel plated copper so it sounds like I would have to even use a higher setting .....
- ridethelightning 1 MW
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Re: kWeld - "Next level" DIY battery spot welder
i think he was talking about straight 0.15 nickel. if you find 0.15 nickleplated copper, let us know!
i have doubts about it though. its used in power tool packs, but when i tried welding it, i think the nickle skin vapourises causing issues, as you need so much current for the copper, the nickle has high resistance and poof!
i have doubts about it though. its used in power tool packs, but when i tried welding it, i think the nickle skin vapourises causing issues, as you need so much current for the copper, the nickle has high resistance and poof!
Re: kWeld - "Next level" DIY battery spot welder
I used just bare copper. I tried plating it also but did not receive any benefits for welding. Needed same current and welds did not get any stronger. Maybe my plating was too thin or something.
I noticed this also. Nickel plating got burned black and maybe little vapor too.ridethelightning wrote: ↑May 27 2019 10:53pmi think he was talking about straight 0.15 nickel. if you find 0.15 nickleplated copper, let us know!
i have doubts about it though. its used in power tool packs, but when i tried welding it, i think the nickle skin vapourises causing issues, as you need so much current for the copper, the nickle has high resistance and poof!
- ridethelightning 1 MW
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Re: kWeld - "Next level" DIY battery spot welder
btw, nickel is toxic as 

Re: kWeld - "Next level" DIY battery spot welder
I do have a sample of some .15 nickel plated copper ....and it is available but not cheap. But useless to me unless I can get good welds with it ...which is why I asked. I tried some at 25j with the stock electrodes and the welds were not good. I will have to try a higher setting or different electrode material to see if I can get good welds. Which is why I asked if anyone has done it to see if they could suggest the proper setting.
Re: kWeld - "Next level" DIY battery spot welder
I think you need at least 75j depending on your battery amps and other thingsHeadrc wrote: ↑May 27 2019 11:22pmI do have a sample of some .15 nickel plated copper ....and it is available but not cheap. But useless to me unless I can get good welds with it ...which is why I asked. I tried some at 25j with the stock electrodes and the welds were not good. I will have to try a higher setting or different electrode material to see if I can get good welds. Which is why I asked if anyone has done it to see if they could suggest the proper setting.

- ridethelightning 1 MW
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Re: kWeld - "Next level" DIY battery spot welder
try making some tungsten tips.
1.5mm tig electrode,(use non radioactive zirconium ones
) drill a hole in copper rod with drill press, slowly bit by bit, use oil. press fit the electrode in, cut off excess with grinder(i make mine~10mm long.
ball the end with the grinder or sanding machine etc.
1.5mm tig electrode,(use non radioactive zirconium ones

ball the end with the grinder or sanding machine etc.
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Re: kWeld - "Next level" DIY battery spot welder
Quick update I received my K-Weld after few welds liquid came out. First i thought this was Water from previous use but turned out it came from the "Lanzhd" Cell.
I had the setting on 9.5 Joule automatic
However i reduced up to 2.5 Joule and worked better.
I measured the Cell voltage and still seem to be good, should i be careful with the leaked Cells?
I had the setting on 9.5 Joule automatic
However i reduced up to 2.5 Joule and worked better.
I measured the Cell voltage and still seem to be good, should i be careful with the leaked Cells?
Re: kWeld - "Next level" DIY battery spot welder
When electrolyte comes out and air gets in the cell should be disposed of. It might hold voltage but likely it will have lower capacity and it will age quickly. There is also concern about fire-safety..Compoundbike wrote: ↑Jun 08 2019 2:39pmQuick update I received my K-Weld after few welds liquid came out. First i thought this was Water from previous use but turned out it came from the "Lanzhd" Cell.
I had the setting on 9.5 Joule automatic
However i reduced up to 2.5 Joule and worked better.
I measured the Cell voltage and still seem to be good, should i be careful with the leaked Cells?
Electrolyte smells horrible, you cant confuse it with water..
Re: kWeld - "Next level" DIY battery spot welder
if it leaked you need to toss it immedialy out. i mean litteraly out the door.
Lithium beats liquid dinosaurs.
- Compoundbike 10 W
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Re: kWeld - "Next level" DIY battery spot welder
Is that normal that the K-Weld can burn through the Battery that Electrolyte comes out? Probably Not.
So has this happened to Someone else?
So has this happened to Someone else?
Re: kWeld - "Next level" DIY battery spot welder
New firmware versions have anti arc features that reduce the risk of puncture but it's powerful and capable device so with too much energy it melts through. That's why it has adjustable outputCompoundbike wrote: ↑Jun 08 2019 5:19pmIs that normal that the K-Weld can burn through the Battery that Electrolyte comes out? Probably Not.
So has this happened to Someone else?

- Compoundbike 10 W
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Re: kWeld - "Next level" DIY battery spot welder
Yes but like i said 9,5 Joule after Calibration had enough power to burn.
Tomorrow i will do more welds with 2,5 joule on 0.15 mm Nickel. Besides that everything is fine.
Tomorrow i will do more welds with 2,5 joule on 0.15 mm Nickel. Besides that everything is fine.
Re: kWeld - "Next level" DIY battery spot welder
what power source(battery) do you have?
and how much amps does kweld show on calibration?
and how much amps does kweld show on calibration?
Re: kWeld - "Next level" DIY battery spot welder
That has nothing to do with kweld, any high power welder will puncture cell walls if set too high.Compoundbike wrote: ↑Jun 08 2019 5:19pmIs that normal that the K-Weld can burn through the Battery that Electrolyte comes out? Probably Not.
So has this happened to Someone else?
Even a crappy aliexpress welder can do that.
Lithium beats liquid dinosaurs.
Re: kWeld - "Next level" DIY battery spot welder
with 2-10J burning holes in a cell?
i played around with 130/150J and wasnt able to shot a hole in a cell.(2000a on calibration and 1700 on real welds)
post some pics of your 2-10J welds please.
i played around with 130/150J and wasnt able to shot a hole in a cell.(2000a on calibration and 1700 on real welds)
post some pics of your 2-10J welds please.
- Compoundbike 10 W
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Re: kWeld - "Next level" DIY battery spot welder
Okay how should I say.. First there's a touch with some sparkles after that there's a good weld with nickel plate melting, but at the same time liquid is coming out.
*edit* also twice a small flame came out.

https://i.ibb.co/sqVjjyQ/IMG-20190609-121130.jpg

*edit* also twice a small flame came out.

https://i.ibb.co/sqVjjyQ/IMG-20190609-121130.jpg
Re: kWeld - "Next level" DIY battery spot welder
holy cow. stop trying anything and get in contact with frank.
theres something wrong.
that looks more like 250J to me.
the heatshrink on the upper cell is melted/shrinked (!)
every cell your tried i would not use for a battery pack. sort them out.
thats 30J :
theres something wrong.
that looks more like 250J to me.
the heatshrink on the upper cell is melted/shrinked (!)
every cell your tried i would not use for a battery pack. sort them out.
thats 30J :
Last edited by Merlin on Jun 09 2019 7:12am, edited 1 time in total.
- Compoundbike 10 W
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Re: kWeld - "Next level" DIY battery spot welder
Battery source is the recommended 3s 5000 mAh from Hobbyking.
.
Okay i will try something else, if it doesn't help i will contact him.
.
Okay i will try something else, if it doesn't help i will contact him.
Last edited by Compoundbike on Jun 09 2019 7:36am, edited 1 time in total.
Re: kWeld - "Next level" DIY battery spot welder
That looks bad. Under 20J there should not be any burning or discoloration with 0.15mm nickel in my experience. Can your calibration be that badly off?Compoundbike wrote: ↑Jun 09 2019 7:00amOkay how should I say.. First there's a touch with some sparkles after that there's a good weld with nickel plate melting, but at the same time liquid is coming out.![]()
*edit* also twice a small flame came out.

Only time I have burned hole through is when I accidentally double tapped foot switch and fired 2 pulses in a row at the same place. Sometimes when electrodes are in bad contact and/or burned black it makes sparks and arcs and that can also make holes and is little scary..
Re: kWeld - "Next level" DIY battery spot welder
that is not 2J, that looks like 200J+.Compoundbike wrote: ↑Jun 09 2019 7:00amOkay how should I say.. First there's a touch with some sparkles after that there's a good weld with nickel plate melting, but at the same time liquid is coming out.![]()
*edit* also twice a small flame came out.
https://i.ibb.co/sqVjjyQ/IMG-20190609-121130.jpg
either your callibration is wrong or your battery supply needs attention.
Lithium beats liquid dinosaurs.
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Re: kWeld - "Next level" DIY battery spot welder
Okay i found the problem. I had calibrated(shortcutted) through a nickel stripe which caused the problems.
Maybe the inventor should put up the warning, so any other people shouldn't pay "learning Money" by making stupid mistakes like me.
I have punctured about 10 cells.
HbPowerwalls video helped me, to get the idea where the problem could have been.
Maybe the inventor should put up the warning, so any other people shouldn't pay "learning Money" by making stupid mistakes like me.
I have punctured about 10 cells.
HbPowerwalls video helped me, to get the idea where the problem could have been.
Re: kWeld - "Next level" DIY battery spot welder
The instructions the come with the kweld are pretty clear i have to say..... 

Lithium beats liquid dinosaurs.