BOSS LEVEL CUSTOM SPOT WELDER

[cheapcookie]

very nice,


You must be very happy of which spot welder you bought after making such a nice pack !

Rojitor the happiest korean spot welder customer

 

[rojitor]

What thickness of copper?

Looks like an excellent pack.

Tom

0.1 copper. That is the best to work with.

 

[rojitor]

I have been doing the first charges and tests today. It has enormous power.

 

[crossbreak]

nice work on welding the copper! I have to try this as well with my LeadAcid welder i build years ago And I will definitely steal the one hand dual electrode idea

where can I get those hexagonal cell spacers? you used for your 22s pack?

I have been doing a rather big pack today with my boss welder. A triangle 22s 6p pure copper pack.

 

[rojitor]

They are very expensive yet worth every penny. I love them.
You can find those here:
http://s.aliexpress.com/RJFRZJzu

 

[rojitor]

I just edited the video of this battery.
[youtube]hrvplvwQM7s[/youtube]

Temporary link https://vid.me/k2kWV

enjoy

 

[wire.rat]

I will be ordering one of this to get more power in my welds without tripping the circuit breaker

 

[rojitor]

I had a sunkko some time ago. The first time I used it my breaker tripped. Then I made sure the oven, washing machine and everything in general was off. It never tripped again.
Of course with a custom welder like this you will not have that kind of problems

 

[wire.rat]

I've just placed an order for 2 of those welders with ems shipping. Could u tell me the size of the cooling fans that u are using?

 

[rojitor]

40 x 40mm
http://s.aliexpress.com/InQnY7J3
The Shopping list is at the description of the mod video.
[youtube]aj5TiHdT5vM[/youtube]

 

[rojitor]

I couldn't find 60x40 mm heatsink so I used two 40x40
http://s.aliexpress.com/6R7fURN3
This is the one aulakiria uses

 

[wire.rat]

Thanks for the info! I was expecting 1 -2 weeks via ems to Singapore, But it took 4 days instead :shock:

[img]https://i.imgur.com/zcsd7fN.jpg[/img]

 

[izeman]

and the good thing: it was only $25 (based on customs declaration)

 

[rojitor]

I got mine very quick too. I guess the korean post office is very efficient.
Share with us your experience with the machine.
Pics and videos are welcome.

 

[progrock]

I just started looking into getting a spot welder, so I can build my own ebike battery... and this definitely looks like an interesting option. I was originally looking at the Sunko 709AD, but my biggest concern (aside from it being defective) is that my apartment's ancient wiring/fuse box is not going to be able to handle the initial current (given I've never blown a fuse, but this place has those old school screw in fuses which I'd like to not blow... not as convenient as flipping a switch to fix).

It seems like there are a few other options, there is this, then I also saw the JP spot welder, and the kWeld. I'm not familiar enough with any of these to know which is "superior".... but the kWeld appears to be out of stock, so at least for now, I guess it's not an option. I also saw some other DIY style options.

Given the thread I'm posting in, I suppose there may be some bias... but I'm currently leaning towards trying this out. TBH, if I thought my fuse box could handle the Sunko 709AD, I'd probably go that route... but with the foreseeable problems there... do you guys think this is a good option?

Currently I'm planning on getting some Bosch 18v 6.3aH batteries, and gutting them for the 20700 cells (and possibly also trying to reuse the plastic cradle for both stability and cooling purposes... tho I also have a 3d printer and am considering designing some custom plastic holders myself). Those 20700 cells are rated at 30amps each, I'm hoping to make a 52v battery that can handle 50amps continuous discharge, while keeping the battery as small as possible (I am concerned with power and weight, far more than I am with distance.. plus can always make a second battery for longer trips). I suppose I could technically make use out of the laser welded copper connectors already on the Bosch batteries... where i could theoretically cut them and solder back together (where I would be causing minimal damage soldering, since it wouldn't be directly on the battery). But I think it's probably a good idea to invest in a spot welder to give me more options.

BTW, if it makes a difference, I am in the US.

 

[rojitor]

If you are not confident on your electrical instalation do not go for a wall plug option. Your breakers will trip all the time. Some people reported that kind of issues.
I am more than happy with this welder because of the size and performance.
As I said in my first post this is not a sales thread and no one will try to convince you to buy it. Buy what you think is best for you, or make your own with a m.o.t. It's Plenty of tutorials on the web.
Other options:
https://malectrics.eu/
https://endless-sphere.com/forums/viewtopic.php?f=14&t=89039
https://endless-sphere.com/forums/viewtopic.php?f=31&t=81274&hilit=6pence&start=0
https://endless-sphere.com/forums/viewtopic.php?f=31&t=68865
Build your own:
https://github.com/KaeptnBalu/Arduino_Spot_Welder_V2

[youtube]hAM6w3o-4kE[/youtube]

Being in usa will be good or bad depending on shipping times and customs fees.

 

[progrock]

Thanks for the quick response... I ordered one... tho I think its a week long holiday in Korea, so might take a bit longer. Next up is getting some nickel and/or copper plate. Is copper recommended over nickel?... and with nickel is .2mm fine, or do I need to go down to .15mm?... as far as copper, I take it I should only go .1mm. (I wonder which is better .2mm nickel or .1mm copper)

Guess I also gotta grab a battery. Is 4S pushing it, and 3S a better idea?... Amazon has a good deal on a 3S 75C 1300mAh battery... that is, if 1300mAh will be enough to not have to charge it every 5-10min.

Also gotta grab some large shrink tubing... gotta figure out what sizes I should get.... seems like there's quite a few options on aliexpress.... I guess I'll grab a few sizes... just wonder how large I will need to go... seeing some 200+ mm diameter options.

Then I just need to settle on the battery cells I'm gonna go with... definitely considering getting a few of these bosch 18v 6.3Ah batteries to tear down... 20 x 20700 30A cells for $110 shipped seems pretty damn good (especially if I can benefit from the battery holder and even the copper strips pre-laser welded on them). Tho I'm also considering jsut getting some 3500mAh GA, or 3000mAh 30Q cells as well... both are pretty cheap and seem like good options as well. But Im thinking these 30A 20700 cells might be ideal for a light weight, high wattage, short distance pack.... where I can then use the GA or 30Q cells for a secondary pack for longer trips.

 

[rojitor]

0.1 copper is the best of the best. But I do not recommend it at all because of all the issues it involves.
0.2 nickel is very easy to do with this welder. The machine does not sweat and the heat is easy to keep under control.
This welder was designed to work with nickel. So the creator does not support nor recommend other metals.
I proved it is capable of much more but that has a price. The heat at 4s is high so the life span of the fets will be shorter than expected. I know the risks and accept them. I will keep using copper no matter what but I do not recommend it.
I hope my explanation does not look contradictory.
I recommend you to stick with 0.2 nickel and 3s lipo. The performance is flawless and very easy to operate. The nickel is cheap and easy to find.

 

[progrock]

Ironically, as contradictory as your answer was... it totally makes sense. Looks like Ill be getting some .2mm Nickel.... now I just need to decide on a width... I;m think around 8mm sounds like a decent choice, or maybe 10mm... pretty much every width from 1mm to 20mm is available.

Tho, the battery cells I'm planning on using already have a copper plate laser welded on them that I may try to get use out of.....

 

[rojitor]

Are you going to weld nickel on copper? If that's your plan you will need to do some testing first.
You will need to rise the flux current times considerably and the number of pulses X multiplier.
Nickel on steel good
Nickel on nickel good
Nickel on copper weak
Copper on steel good
Copper on copper very weak (unviable)

 

[rojitor]

I just did it for you out of curiosity.
Nickel on copper with 3s is very weak.
4s 7ms X2 makes very good welds. Seems you will need the same power as copper on steel to do it.

From right to left
At the right of the tabs I did 3 spot welds on 3s 12,14 and 16ms
At the left I did 4s 6,7 and 8 ms the results are as clear as daylight.

 

[progrock]

Wow... hugely helpful.... was originally thinking copper on copper would seem to make more sense... tho obviously was gonna see if that was viable first.

So, with a 4s battery and some abuse to this spot welder... nickel on copper could be possible. Do you think steel on copper would make more sense... I'm not very familiar with the conductivity of nickel vs steel (tho I suppose not the hardest thing to look up)... obviously I figure nickel is so highly used, that it's usually a good choice. As I mentioned, the only reason I'm considering copper is based on the battery packs I'm planning to teardown to build my cell. Obviously Bosch has some serious industrial manufacturing hardware (and I think it's fair to say makes a very high quality product). Obviously I'll have to do more planning and testing, but it seems like it would make sense to try to utilize what's already on the battery... if possible. Of course I can always remove their copper tabs and just go with straight nickel... but will see when I get to that step.

I'm also interested in seeing this welder up close. It may also be possible to beef it up a little if I'm going to be abusing it with a 4s battery and longer weld times. It's about time I make some use out of my electrical engineering degree, lol. But waiting to see it, and get a better understanding of what it consists of before I make any plans.

Thank you so much for all the help so far... it has been extremely useful.

 

[wire.rat]

. I'm also interested in seeing this welder up close. It may also be possible to beef it up a little if I'm going to be abusing it with a 4s battery and longer weld times. It's about time I make some use out of my electrical engineering degree, lol. But waiting to see it, and get a better understanding of what it consists of before I make any plans.

I've got 2 of this welder so I could post some high quality photos for u.

Isnt this spot welder is just a arduino that is controlling a bank of FETs connected to a LiPo? I'm sure you could add more FETs to the spot welder, but there barely any space internally to solder the FETs to, so perhaps a better option would be just to wire up another bank of FETs and use this spot welder to control the timing of the FETs switching on and off. There's another thread somewhere about using a zener? and TVs diode to prevent the inductance of the Battery wire and spot welding probes wire from causing avalanches current that damage the FETs, so look into that as well.

I think that you can use the screw and nut(compressions) method to secure a new bank of FETs to a 1 or 2mm thick copper plate and attach your new set of spot welding probes to it. And hookup the gate and source (or was it gate and drain?
I don't have a electrical engineering degree) to the spot welder to control the timing

 

[rojitor]

Wow... hugely helpful.... was originally thinking copper on copper would seem to make more sense... tho obviously was gonna see if that was viable first.

So, with a 4s battery and some abuse to this spot welder... nickel on copper could be possible. Do you think steel on copper would make more sense... I'm not very familiar with the conductivity of nickel vs steel (tho I suppose not the hardest thing to look up)... obviously I figure nickel is so highly used, that it's usually a good choice. As I mentioned, the only reason I'm considering copper is based on the battery packs I'm planning to teardown to build my cell. Obviously Bosch has some serious industrial manufacturing hardware (and I think it's fair to say makes a very high quality product). Obviously I'll have to do more planning and testing, but it seems like it would make sense to try to utilize what's already on the battery... if possible. Of course I can always remove their copper tabs and just go with straight nickel... but will see when I get to that step.

I'm also interested in seeing this welder up close. It may also be possible to beef it up a little if I'm going to be abusing it with a 4s battery and longer weld times. It's about time I make some use out of my electrical engineering degree, lol. But waiting to see it, and get a better understanding of what it consists of before I make any plans.

Thank you so much for all the help so far... it has been extremely useful.

Nickel plated steel probably welds easier than pure nickel. I do not have 0.2 plated so I can't test it. Nevertheless pure nickel is always better.
Do not remove the copper tabs. Most probably you will destroy the cells and lose a very conductive base. You better weld on the copper.

 

[rojitor]

. I'm also interested in seeing this welder up close. It may also be possible to beef it up a little if I'm going to be abusing it with a 4s battery and longer weld times. It's about time I make some use out of my electrical engineering degree, lol. But waiting to see it, and get a better understanding of what it consists of before I make any plans.

I've got 2 of this welder so I could post some high quality photos for u.

Isnt this spot welder is just a arduino that is controlling a bank of FETs connected to a LiPo? I'm sure you could add more FETs to the spot welder, but there barely any space internally to solder the FETs to, so perhaps a better option would be just to wire up another bank of FETs and use this spot welder to control the timing of the FETs switching on and off. There's another thread somewhere about using a zener? and TVs diode to prevent the inductance of the Batteras y wire and spot welding probes wire from causing avalanches current that damage the FETs, so look into that as well.

I think that you can use the screw and nut(compressions) method to secure a new bank of FETs to a 1 or 2mm thick copper plate and attach your new set of spot welding probes to it. And hookup the gate and source (or was it gate and drain?
I don't have a electrical engineering degree) to the spot welder to control the timing

In a chat with Aulakiria some time ago he told me that this machine could be incredibly powerful with more fets and maybe higher rated ...but that would make it considerably bigger and expensive. Since he designed it for nickel and wants it to be as small and affordable as possible he does not plan to do it. Besides it could be kind of dangerous. The automatic machines of the battery factories do not have the fingers of the operators that close.