okashira
10 kW
Doh. Look at the fets closely, take a pic.Craigh85 said:
JP spot-welder, FET-switched, timed adj. pulse
- Thread starter okashira
- Start date
Right, see if there is voltage on the probes before the foot pedal is activated. If the FETs blow, they generally short so you'd see 12v on the probes all the time.
Offroader said:
That might help if you are running really high amps. It gets a little trickier to make them all turn on and off at exactly the same time, which is mostly a function of the board layout.
The same timing and driver circuit should work with more FETs.
okashira
10 kW
dnmun said:
Voltage becomes quite relevant because at welding current (3k amps) the voltage drops of the connections, wires, and actual weld become quite significant
How does pulse time affect current/amps and the fets? You mention 3K amps, but is that at a certain pulse?
Because I blew my fets when I turned my pulse time higher in the 15-20 range, I was fine with a lower pulse time.
If you are running high amps by using more batteries, should you keep the pulse time below say 10 seconds?
Because I blew my fets when I turned my pulse time higher in the 15-20 range, I was fine with a lower pulse time.
If you are running high amps by using more batteries, should you keep the pulse time below say 10 seconds?
okashira
10 kW
Offroader said:
No, pulse time does not affect current.
that is why the professional welders allow you to adjust voltage.
But they are $3000 so...
I was very sad to read that Jakov can't offer his welders any more at the moment.
Hope he gets well again soon!
I was lucky enough to still get one - but others are looking for alternatives.
Until he is offering his welder again, this might be interesting:
Today this popped up in my FlipBoard-reader:
The "KaeptnBalu"-welder
A nicely designed and very affordable DIY Welder project based on an Arduino:
http://www.instructables.com/id/DIY-Arduino-Battery-Spot-Welder/
It has a double-pulse and even a tiny display.
On Github he publishes all the files down to detailed Excel-Part listings and even a premade Shopping-List
Total cost with many parts bought in Europe is around 50$.
This includes the price for 10 PCBs from pcbway.com .
Currently he offers to sell his surplus PCBs for 6Euro incl WW shipping!
Of course there is no long-term experience behind this yet like in the JP-Welder,
but all the pieces are accessible and exchangeable here and even the software is open in the Arduino.
So it looks like a great deal to me to all the other alternatives I have found!
Cheers, Ulli
Hope he gets well again soon!
I was lucky enough to still get one - but others are looking for alternatives.
Until he is offering his welder again, this might be interesting:
Today this popped up in my FlipBoard-reader:
The "KaeptnBalu"-welder
A nicely designed and very affordable DIY Welder project based on an Arduino:
http://www.instructables.com/id/DIY-Arduino-Battery-Spot-Welder/
It has a double-pulse and even a tiny display.
On Github he publishes all the files down to detailed Excel-Part listings and even a premade Shopping-List
Total cost with many parts bought in Europe is around 50$.
This includes the price for 10 PCBs from pcbway.com .
Currently he offers to sell his surplus PCBs for 6Euro incl WW shipping!
Of course there is no long-term experience behind this yet like in the JP-Welder,
but all the pieces are accessible and exchangeable here and even the software is open in the Arduino.
So it looks like a great deal to me to all the other alternatives I have found!
Cheers, Ulli
macribs said:NetPro said:macribs said:
Seems Lipo would work and make for one truly portable spot welder
Any reason why you went for the more expensive nano-tech over the ie cheaper 3s zippy flight or 3s multistar? You could have twice the Ah for the same price and pack should last even more number of welds before charging.
I guess what I am asking is the high C rate of the nano tech Lipo really called for when used for spot welding?
The Man himself --JP-- recommended them to me on January 21st:
"Use 3S 20 Ah nano cells and that should be it!".
Because of an injured back, I cannot lift heavy objects and needed something light weight.
Knowing that the higher the "C" rating the higher the current output (albeit not sustainable for very long) I went for the 130C to make sure I had plenty of juice.
Since I don't plan on building very large packs, how many welds between charging the packs wasn't critical to me.
These HK packs were expensive but they sure are lightweight and provide enough power to weld with short welding times and this was using a bad set of electrodes.
When I finish building my new hand-piece I will post updates.
Hi Riba,
Any idea when you will have these welder will be available for sale again? You should really get a helping hand rather than do it all alone. Seems there is too much demand for these welders 8)
Hope you get better soon.
Take care,
Any idea when you will have these welder will be available for sale again? You should really get a helping hand rather than do it all alone. Seems there is too much demand for these welders 8)
Hope you get better soon.
Take care,
Hi, thank you, but I really don't know! I am feeling better, but doing welders along with my full time job is just too exhausting for me since I have chronic disease. Welders take more time and work then one would think 
I'm thinking about open sourcing this, with full documentation. It still wont be as easy since some parts are more suited for series production, but there are ways to get past that.
I'm thinking about open sourcing this, with full documentation. It still wont be as easy since some parts are more suited for series production, but there are ways to get past that.
marty
10 MW
Ribba wish ya the best with your health. Drink water.
Happy that I got my welder. Never used it but I am ready to continue with my battery building experiments. If you need any help with "open sourcing this, with full documentation" You got a great team of volunteers here on this forum. How does one get a circuit board made? I am guessing some type of computer drawing? Post it here and the "documentation" will happen by itself.
Happy that I got my welder. Never used it but I am ready to continue with my battery building experiments. If you need any help with "open sourcing this, with full documentation" You got a great team of volunteers here on this forum. How does one get a circuit board made? I am guessing some type of computer drawing? Post it here and the "documentation" will happen by itself.
riba2233 said:Hi, thank you, but I really don't know! I am feeling better, but doing welders along with my full time job is just too exhausting for me since I have chronic disease. Welders take more time and work then one would think
I'm thinking about open sourcing this, with full documentation. It still wont be as easy since some parts are more suited for series production, but there are ways to get past that.
Oh man..sorry to hear that. I hear ya...i hardly have time for my own DIY project given how life sucking a full time job can be.
Yeah..given the legacy of JP spot welders, open sourcing it would be an excellent idea. Will be looking forward to it.
Get better soon!
macribs
10 MW
- Joined
- Jul 22, 2014
- Messages
- 3,702
Glad to hear you are feeling better, take of yourself now. You must not set your spot welder gig before your health.
If you can find a way to hire in extra hands, you might be able to keep the shop open? That way you can get some extra bucks as well. Financial security and stability should have priority as you have chronic illness. Don't make such decisions in a rush, take your time a think it over. Then do it again.
If that will not work out for you, open sourcing the spot welder would be much obliged by the community and I feel certain I speak for many others as well.
I wish you the best. Get well!
If you can find a way to hire in extra hands, you might be able to keep the shop open? That way you can get some extra bucks as well. Financial security and stability should have priority as you have chronic illness. Don't make such decisions in a rush, take your time a think it over. Then do it again.
If that will not work out for you, open sourcing the spot welder would be much obliged by the community and I feel certain I speak for many others as well.
I wish you the best. Get well!
Lurkin
100 kW
I wouldn't be afraid to open source.
There will always be relatively lazy people like me who are willing to wait for the real deal!
There will always be relatively lazy people like me who are willing to wait for the real deal!
Thank you guys!
@ marty - I already have the documentation, gerbers etc, just need to organize it a bit so others can understand it easily
Even if I could get help, that's not the whole story, since I'm selling more now there's also a question about legality etc, so I would have to open a business or something, and that would lift up the cost of welders too much, and they wouldn't be cost effective to make them and sell them any more, for both you and me, and I would need to invest even more of my time into it.
So yeah, I can only say that I'm sorry, and that open sourcing will help people who want their own.
@ marty - I already have the documentation, gerbers etc, just need to organize it a bit so others can understand it easily
Even if I could get help, that's not the whole story, since I'm selling more now there's also a question about legality etc, so I would have to open a business or something, and that would lift up the cost of welders too much, and they wouldn't be cost effective to make them and sell them any more, for both you and me, and I would need to invest even more of my time into it.
So yeah, I can only say that I'm sorry, and that open sourcing will help people who want their own.
up0 said:
Looks very interesting. I already bought his (last) set of PCBs, I`ll build it in the spare time - have already bought JP`s welder.
Looking the video on Youtube, I noticed however that there are sparks every time he pushed the pedal. Any idea why ?
> , I noticed however that there are sparks every time he weld. Any idea why ?
Good question - I am not an expert - having only done ~600 welds so far,
but it seems to be very similar to the video that Javok made in the first post of this thread
Screenshot:
I weld with 0.15 pure Nickel and I believe that I see a lot less sparks when I press the electrodes down harder.
If there is a slight gap between the nickel and the battery, I seem to get more & louder sparks.
Maybe someone with more experience can confirm or correct me?
Thanks Ulli
Good question - I am not an expert - having only done ~600 welds so far,
but it seems to be very similar to the video that Javok made in the first post of this thread
Screenshot:
I weld with 0.15 pure Nickel and I believe that I see a lot less sparks when I press the electrodes down harder.
If there is a slight gap between the nickel and the battery, I seem to get more & louder sparks.
Maybe someone with more experience can confirm or correct me?
Thanks Ulli
My spot welder is ready, this is my all LiPo setup. The welder battery is a 3S2P made with 2 5300mAh 3S lipo:
I think I have made good welds of 0.2mm nikel tabs but the electrode stick always to the tab (more the positive one). I have tried 15 and 20ms pw with the same result. Could it be insufficient current?
I think I have made good welds of 0.2mm nikel tabs but the electrode stick always to the tab (more the positive one). I have tried 15 and 20ms pw with the same result. Could it be insufficient current?
I replaced all my fets, and they came out easily by heating all 3 prongs on the back with some added solder and pulling the fet right out. A solder sucker easily takes care of the solder.
Unfortunately my welder still doesn't work.
Green light lights up. But there seems to be no voltage at the probes and nothing welds.
I jumped 5 volts into the MCP 1407 from the PIC +5 volts and the gates are not opening but the green light is constant. I've done this before when I blew my PIC chip and this opened the gates.
I checked continuity between MCP 1407 and gate resistors and all seems fine. Resistances all seem fine.
The solder between the Drain and Source pins are very close (almost touching) but i read 2 million OHMS between the two prongs so I assume it isn't making continuity.
Should I replace the MCP 1407? Anyway to jump voltage to the gates to see if the problem is in the MCP 1407?
Thanks for any advice on what to troubleshoot next.
Unfortunately my welder still doesn't work.
Green light lights up. But there seems to be no voltage at the probes and nothing welds.
I jumped 5 volts into the MCP 1407 from the PIC +5 volts and the gates are not opening but the green light is constant. I've done this before when I blew my PIC chip and this opened the gates.
I checked continuity between MCP 1407 and gate resistors and all seems fine. Resistances all seem fine.
The solder between the Drain and Source pins are very close (almost touching) but i read 2 million OHMS between the two prongs so I assume it isn't making continuity.
Should I replace the MCP 1407? Anyway to jump voltage to the gates to see if the problem is in the MCP 1407?
Thanks for any advice on what to troubleshoot next.
bigbore said:
I noticed the same thing with mine. The electrodes tend to stick a little no matter what. Using more downward force on the tips helps. Rocking the tip back and forth after welding un-sticks them.
The 2M ohm reading is probably just from solder flux residue. Not a worry.Offroader said:
Does the red light blink when you hit the foot pedal?
If not, you could try measuring on the input of the gate driver chip to see if there is a pulse coming from the PIC.
