Sunkko 737G+ Review TLDR: Dont buy it

This is the newest welder from them and I was their first customer to order it So I paid almost 400$ for it and I was pretty happy about it because I would not need to charge and buy new batteries for the boss welder

Its advertised that it can weld up to .25mm pure nickel, BUT that’s only when your welding nickel to the cell, not nickel to nickel. Guess how I found about it…

I used 0.15 nickel and the first layer was great, but as one is not enough, I wanted to put a second layer on the welds would be so weak that I could break them by hand, and it was putting out so much heat that the electrodes would heat up so much that they would bend and become useless after 10 welds that didn’t hold The 70B pen is total crap as well as it can not hold the copper electrodes tightly, after you make one weld they electrodes will stick to the nickel and as you lift the pen they stay on the nickel, but that’s not the worst thing Also the welder is pretty fast to the boss welder since it does not heat up, and can make the first layer of nickel really fast

Also one more big problem is that the welder requires at least a C type 30A fuse, but I put 40A just to be safe that it wont trigger, and that renders your wall outlet useless in terms of protection and safety.

But in the end after spending an hour or so trying to tune the welder, I asked for a refund, and got it, they even covered the shipping back to china. I did not try their other welders, so I can not say anything on them, maybe they are better.

Just save yourself money and time and get a welder from @aulakiria


Did you try to change the copper probes for something with certain purity?

The probes on the machine are not really good, they lasted me for like 15 welds, because they stick really hard to the nickel and I would have to break it And when I would turn the setting harder they would blow a hole in the cell I used the 70B mobile pen

Should’ve tried to swap them out for pure copper rods. Might have done the world of a difference. Had similar problem with a cheaper sunkko. Sanding the tips of the copper helps abit as well.

It is indeed a piece of crap. Mine arrived broken (poor quality control?). The entire transformer is rolling around inside the casing.

Ever since trying to get a refund at but they say the problem is my 40 amp fuse. Crazy ofcourse as the machine is 15 amp and shorts as soon as you plug it in (and still turned off)

Dont buy a 737g, and dont buy anything at because they will screw you over.

Keeps complaining and they wi refund you after like 5 messages I was fightning to get my money returned after I ordered a phone from them for 3 months and it arrived broken and I returned it

@b264 post your step by step please, this guy seems like he would benefit from it :slight_smile:

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@dareno do you have that saved somewhere?

did you pay with paypal or credit card?

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