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Boss level custom spot welder


Don’t blow the fets :joy:


I did intensive testing with other metals. My es thread

I did many battery packs with 0.1 copper. It seems to be the best.
I managed to weld 0.2 copper as well but it damages the fets. I didn’t test 0.15 because it was not in stock.
My tests with aluminium were disappointing. Low flux times have no effect and high times make holes. Besides it is extremely difficult to solder. I’d say impossible without aluflux. Aluminium is very cheap yet I couldn’t find sheets at a reasonable price so I lost interest. Copper is the best.
I shared pics and videos in this very thread and the sphere’s.
Take a look if you have some time.
Be careful with the copper. Proper cooling ,glasses and gloves are a must.
Share with us your experience please.


tell me if i’m wrong but even if it will only do .1mm copper that should be good and I can just use a much wider folded-over tab and get really good conductance.
Looking at chart from the es link I posted above and extrapolating for the use of copper being 4x as conductive, a 28mm folded tab should put me in the green for 48 amps, no?


Yes. With 0.1 copper you can get around that cypher.

Ampacity (Powestream extrapolation)

0.1 is relatively safe for this welder. You will need 4s lipo and 5-6 ms X2 flux time.
Copper on copper makes poor welds so the best option is using wide tabs or solder+weld tabs. I always used wide tabs. The results are outstanding.
All my copper packs are over powerful. Keep in mind:
As I said many times lee designed this machine to be used on 3s with nickel. It is copper capable but you will shorten the lifespan of the fets.
I agree with that. It is totally worth it imho but lee does not support it.
If you engage copper you must asume the risk.


Damn. That chart looks like shit. I am on cell phone.
It should look ok now


ill be comparing charts thanks. but I thought I could get away with 3s with the .1mm copper no? thought I read that and it was the .2mm copper that needed the 4s.


No. 0.1 copper needs 4s.


ive got “5mil” copper, which is.005" which is .12mm copper. You think that will go with 4s?


Sure. I did 0.20 with 4s


thought that blew holes in .2mm Cu?


I did some holes but I succeeded making a battery pack 0.2 copper
I do not recommend it by any means. 0.1 is easier and not so harmful for the boss welder.


I’ve never made a battery pack before and am looking for a spot welder. It looks like these little arduino spot welders are the way to go. I’d like to buy a complete set and am looking at buying alukirian’s version, but It appears malelectric’s version has newer updates. Would you recommend buying one over the other?


I do not own the malectrics… so I can’t tell which is better.
I am very happy with my boss welder. Maybe another member can tell the difference.


And lets not forget the really good soldering ability/parts that come with @aulakiria’s one


True. The hakko is a very good bonus. I use it often.


How much does it cost?


I am not affiliated, associated, authorized, endorsed by, or in any way officially connected with Aulakiria. THIS IS NOT A SALES THREAD. And i have no profit nor gain with this, i just think it’s a nice thing and i am sharing it with you. If you are interested on buying one just mail him saying you want one here that’s his paypal account as well. If you mail him be brief and use only perfect academic understandable english. Something google translator can deal with.
The prices are :
basic set : usd $ 80
Hakko T12 soldering iron Handle & Tip : usd $15 (option)
full set : usd $95
Paypal fees 3.5%, Usd-krw Exchange fees 3%…It is double charged so please consider the option send money to family/friend thank you
shipping method

  1. Global RR (KOREA post registered airmail) : $15 (20~40 business days)
  2. Global EMS fee : $25 (10~15 business days)
    more info here:


Thank you !:ok_hand:


Google translated to English


About to order one for myself, does anyone know what the, “Amount of Customs declaration” should be?