JP spot welder

[riba2233]

Peak of course, max pulse time is 20 ms.

 

[bigbore]

I do not know if it has already been asked before.
If it were used a capacitor connected in parallel to the poles of the battery this would bring some advantage to have an instantaneous rate of current?

 

[riba2233]

Maybe, but we use batteries that can give enough peak current. Capacitors are too expensive (at least ones which actually do their job properly).

 

[TheBeastie]

I do not know if it has already been asked before.
If it were used a capacitor connected in parallel to the poles of the battery this would bring some advantage to have an instantaneous rate of current?

You could try your luck on these Chinese ones there seem to be more and more showing up on ebay. Some list the most crucial ESR spec which will determine if its going to dump the power like a lightening bolt or dribble it out like a lemon.
http://www.ebay.com/itm/2-7-V-500F-Farad-Ultra-Capacitor-/111739642268?hash=item1a0433a19c
http://www.ebay.com/itm/1Pc-500F-Farad-Electric-Double-Layer-Capacitor-Super-Ultra-Capacitor-2-5V-/371160761281?hash=item566ae7c3c1

A not so good ESR Chinese cap might actually be beneficial as some one in this thread built a lipo pack battery for his ribba-spot-welder but it was too much power and was hurting it I believe?

You can always hook it up to a watt meter to test capacitance and do a paypal refund if you get less then 5% of your expected farads.
I remember doing a discharge test on a cap bank that showed to give about 5.5Whrs from a 15volt 233 farad ultracapacitor bank which from calculations was about right from memory. Looking at the video I think I remember I couldn't be stuffed waiting for it to fully discharge so I stopped at 5.5whrs.
Just looked it up again and absolute peak charge up should actually give 7.2Whrs), I use it for various little things but mostly to start a ride on lawn mower.
https://www.youtube.com/watch?v=1kBpH2Lr2lA

 

[riba2233]

These capacitors probably have to high IR. And yeah, good point, if capacitor had too low IR, that could be a problem.



Anyway, I've just successfully tested welder from new batch, it works like it should, and here are some quick pictures: (NOTE: actual welders will have green PCB!)

There will also be a protective clear shrink wrap supplied.

 

[marty]

Will there be a plastic case like the spot welder on page one?

 

[riba2233]

No, there wont. Box was one of two main reasons why assembly was too complicated and took too much time.

 

[jamesonotc]

No, there wont. Box was one of two main reasons why assembly was too complicated and took too much time.

Do you have an ETA of when you will have spot welders ready to purchase/ship?


I'm sure someone will work up a 3d printed case in no time.

 

[riba2233]

I have a 3D printer, but it's not worth it for series production. If someone has time/money/will he can do it, but my goal is to offer product at acceptable price

It will take about two weeks till I get my PCB's.

 

[tomjasz]

Jeebus! JP is simply the most reliable builder of welders to date. I'm amazed at the willingness to cater to those insistent on reinventing the wheel. LOOK, this is simply the simplest most reasonably priced welder available to a hobbiest. Buy it. As is. Quit trying to shave pennies. You'll not be disappointed.

 

[jamesonotc]

It will take about two weeks till I get my PCB's.

Would you mind confirming that those who have requested to be on your list will have access to this first round of new PCB? Or is there limited quantity available?

 

[riba2233]

It will take about two weeks till I get my PCB's.

Would you mind confirming that those who have requested to be on your list will have access to this first round of new PCB? Or is there limited quantity available?

Don't worry, you are near the top of the list But this time quantities are not limited, although there is a limit on how fast I can make pack them and ship them, but otherwise, no limits

@tomjasz: thank you for kind words!

 

[jamesonotc]

Don't worry, you are near the top of the list

Thanks riba! good work and looking forward to hearing from you!

 

[9lives]

Ribba, absolutely fantastic work. It looks great and can't wait to get my hands on one. Goodbye lipo's, hello 18650's.

 

[riba2233]

Thank you, that is really nice to hear

One of my main goals was to direct people to using 18650 cells which got much better and cheaper in past two years.

 

[marty]

Like that the new spot welder can bolt directly to the battery terminal and not flop around on a flexible cable like the old model.

There will also be a protective clear shrink wrap supplied.

Hope this protects the little parts from getting banged around and broke. I have seen some really thick and strong shrink wrap. I be happy with clear or any color.

I'm sure someone will work up a 3d printed case in no time.

Please put me on the list for a 3d printed case.

 

[riba2233]

Yeah, I have that thicker heat shrink, the right stuff

 

[18650dude]

Nice kit! Are you using a micro-controller for the timing or analog parts?

 

[riba2233]

Thanks! Yeah, I use PIC microcontroller.

 

[dfr]

Hi Riba.

It sounds like your new welder isn't too far away but do you have any of your old welders for sale now, doesn't have to be new? Or maybe someone wants to sell one after finishing a project?

Also will there be any functional improvements in what your new welder can do?

Cheers

 

[riba2233]

Unfortunately no, I've sold out all of the old and prototype units.

Functionality is the same, only the design is different.

 

[206monkey32]

RIBA,
Add me to the list if you please. This is awesome.

 

[riba2233]

Thank you! It's awesome that you think it's awesome

 

[18650dude]

These welders are so good. I don't think anyone who own one will want to sell. Made a battery pack a month ago and it working perfectly with no issues.

 

[destro23]

Riba, hope i'm still on your list somewhere!

thanks for the hard work!