kWeld - "Next level" DIY battery spot welder

BVH said:
Got my firmware update tool today but am having a problem accomplishing the update. Adapter is communicating with PC as it should and is Com10 as verified by plugging and unplugging and seeing it appear, disappear and reappear while watching in Device Manager. the putty software launches fine and I input Com10 and 115200, Serial. When I click the button, a new window appears just like in the instructions but the window indicates "offline" instead of "connected". Cannot type the "k" nor anything else in the window. Repeated attempts result in the same thing. I assume the welder does not have to be powered up with the battery power supply as noting is said about doing so. I gotta be missing something simple, right?
Sounds okay (the online/offline info is for dialup connections AFAIK). But the welder must be powered! It is okay to use the battery for that, there is no risk to blow things up, just make sure that the electrodes are separated.
 
tatus1969 said:
BVH said:
Got my firmware update tool today but am having a problem accomplishing the update. Adapter is communicating with PC as it should and is Com10 as verified by plugging and unplugging and seeing it appear, disappear and reappear while watching in Device Manager. the putty software launches fine and I input Com10 and 115200, Serial. When I click the button, a new window appears just like in the instructions but the window indicates "offline" instead of "connected". Cannot type the "k" nor anything else in the window. Repeated attempts result in the same thing. I assume the welder does not have to be powered up with the battery power supply as noting is said about doing so. I gotta be missing something simple, right?
Sounds okay (the online/offline info is for dialup connections AFAIK). But the welder must be powered! It is okay to use the battery for that, there is no risk to blow things up, just make sure that the electrodes are separated.

OK, thanks! I didn't want to let any Magic Smoke escape so figured I'd ask first.
 
OK the flash to 2.8 was successful. I then got part way into the CAL procedure and got a phone call. Was on it for about 3 minutes and when I returned, the screen still read SHORT! so I resumed by holding the probes together and pressing the foot pedal. I got a significant flow of current, looking like full welding current with sparks. Not good. I then rebooted and went thru the CAL procedure again getting 2.69 but when I released the foot pedal the rotating data disappeared and "CAL" was on the display. I rebooted, no change. Goes to CAL. I reflashed with the same results. (adapter is not connected during all this) I rotated the encoder to EXIT and pressed the knob but it always returns to CAL

EDIT add: Just reflashed down to 2.7 with same results. I'm stuck in CAL.
 
BVH said:
OK the flash to 2.8 was successful. I then got part way into the CAL procedure and got a phone call. Was on it for about 3 minutes and when I returned, the screen still read SHORT! so I resumed by holding the probes together and pressing the foot pedal. I got a significant flow of current, looking like full welding current with sparks. Not good. I then rebooted and went thru the CAL procedure again getting 2.69 but when I released the foot pedal the rotating data disappeared and "CAL" was on the display. I rebooted, no change. Goes to CAL. I reflashed with the same results. (adapter is not connected during all this) I rotated the encoder to EXIT and pressed the knob but it always returns to CAL

EDIT add: Just reflashed down to 2.7 with same results. I'm stuck in CAL.
If you keep the foot pedal down during SHORT test, the display will show you the result. Please post that info, this will allow diagnosing what happened.

BVH said:
I got a significant flow of current, looking like full welding current with sparks. Not good.
That's what is supposed to happen. The SHORT test uses a high current pulse for measurement. But if you get sparks then you either have dirty/oxidized electrodes, or are not pushing hard enough. Make sure that all nuts and bolts are tight, and may be clean the tips with fine sand paper.
 
Hi there,
I've just bought your welder. Yesterday I made ca.50 weldings 50J. I was so happy. Fast & clean. But tomorrow morning I'am receiving an errror just afer turn on. I tried to disconnect a foot pedal and changed a battery, the same problem. See yt video please.What does it mean? Could you help me to solve this problem asap.
Thx a lot Darek
www.youtube.com/watch?v=V1taERfrH70&feature=youtu.be
 
DeZir said:
Hi there,
I've just bought your welder. Yesterday I made ca.50 weldings 50J. I was so happy. Fast & clean. But tomorrow morning I'am receiving an errror just afer turn on. I tried to disconnect a foot pedal and changed a battery, the same problem. See yt video please.What does it mean? Could you help me to solve this problem asap.
Thx a lot Darek
www.youtube.com/watch?v=V1taERfrH70&feature=youtu.be
This means that either the power MOSFETS have shorted, or one of these diodes:


The diodes are more likely, do you have the equipment to remove them and check if the problem disappears? You can use your kWeld power source for testing, but please do *not* make welds without the diodes.

It can be material defect, but in could also be that you have touched different poles with the electrodes on the battery that you are welding. When this happens, then you feed current back into the welder, and these components are usually the first ones that fail. I already have a note to add this warning in the documentation, but haven't had time to edit it yet.
 
"Encodergate" is finally over. I switched production to a new type (after having disassembled one to see the internal construction): EN11-HSB1AF15. We have also replaced these parts in the entire existing stock.
 
eee291 said:
I welded a 300 Cell Pack with the stock cables just fine.
You need to have the Welder above the Cells, similar to this:

file.php

Do you have more information on this weld head system in the picture? Have you done a post anywhere else about this. I am very interested : )
 
https://endless-sphere.com/forums/viewtopic.php?f=14&t=89039&start=400#p1406999a


It's not mine, I'm just planning on making something similar using a drill stand.
 
PaulD said:

Hi PaulD,

I am interested in your parallel gap spot weld head setup. Did you do a thread anywhere on this unit? I would like to produce one very similar for my personal use. Looks like some of the parts where 3D printed? Thanks in advance for any information.

Bob
SMS text 519-636-6636
 

Hi tatus1969,

What is the oldest hardware version of the kWeld that can be updated with the new firmware and has all the features of the new r3.2/1804 (or what ever is the current model)?

Ok I found the kWeld rev2 upgrade.pdf and it seems the "new voltage regulator with an extended input voltage range of 4V - 30V" can't be upgraded on the r2 boards. Is r3/1710 the first r3 version?
 
bobmutch said:
What is the oldest hardware version of the kWeld that can be updated with the new firmware and has all the features of the new r3.2/1804 (or what ever is the current model)?

Ok I found the kWeld rev2 upgrade.pdf and it seems the "new voltage regulator with an extended input voltage range of 4V - 30V" can't be upgraded on the r2 boards. Is r3/1710 the first r3 version?
The voltage regulator on rev1/rev2 has a completely different topology (buck, whereas rev3 is SEPIC), which is why it cannot be upgraded easily. And rev1/rev2 uses a potentiometer instead of a rotary encoder. Rev3 has improved inductive kickback protection via additional TVS diodes. Rev3.2 has an onboard temperature sensor for MOSFET Rdson compensation, and rev.3.3 has received a second big TVS diode.

The firmware is compatible with all rev3 board revisions and will detect which one it is running on. It should also work on rev2, but it needs to be configured manually whether to use a potentiometer or a rotary encoder.
 
Just to close this out from my earlier post....Frank advised me I had too much current available with the two paralleled 3S/6000 Grapheen packs to accomplish the calibration. I was flowing 1996 Amps which triggered overcurrent.

bought a Hobbyking Grapheen 3S/6000 Panther which is the 75C rated pack instead of the 65C rated Grapheen packs I already have and were using before to try to calibrate. I used the single Panther pack to calibrate the Kweld and it solved my problem of too much current with the other two 65C paralleled packs. I had a current flow of 1679 Amps and resistance of 2.22 Milliohms with the single Panther pack.

I should mention that HK is having a site-wide, 20% off sale this weekend. I just bought another 3S/6000 75C rated Panther for $59.xx out the door, free shipping. GAMEON is the code.
 
ossivirt said:
First welds. Did not have nickel or cells at hand so here is steel washer to 0.8mm steel wire (welding filament). I made battery leads from 6avg because that is what I had. Yea I over did it with the glue. Somehow I missed that there is detailed instructions for assembling the housing :confused:
IMG-20190111-WA0001-870x1546.jpeg
IMG_20190111_175416-870x1160.jpgIMG_20190111_175418-870x1160.jpgIMG_20190111_175414-870x1160.jpg
How are my values? I think those are pretty good for old lead acid battery.. Next I try nickel strip and maybe brass and copper..
I was finally able to make some welds for testing purposes to test materials and capabilities of the welder.
View attachment 2_20190202_131756-1745x915.JPG
50j was maybe little much for 0.1mm materials so I tried with 45j and it was little better in my opinion. 0.1mm copper was both cases very easy to remove. 0.1mm brass was a bit better and 0.2mm brass actually felt best because it welded with same current level as 0.1mm copper and material itself and welds felt like 3x stronger. Nickel welded nice at 20j and as you can see almost impossible to rip off.

I also tested 0.2mm copper but that needed 150j to make any kind of weld and at that energy level it almost burned through the olfa blade so that might not be good for negative end of 18650 cell.. And after just a few welds you can feel the energy in the warm cables..

This test was made for my reference to understand and choose right energy levels for different materials in the future but I thought someone could find it useful as well. Next I am planning to nickelplate some copper but since brass seemed to work so well I am not sure if electroplating is worth the effort.
 
Hi,

Dislaimer: I’m a simple customer that wants to have a good spot welder for mostly 0.15 Nickel strip on 18650 batteries – I guess your average guy looking for a good product reasonably priced without too much hassle – and have only limited/functional knowledge on all the electronics behind this.

I am considering buying the whole bundle (kWeld complete kit cables assembled + kWeld laser cut housing kit + kWeld firmware update tool + kCap ultracapacitor module complete + kCap laser cut housing kit).

And I have a few questions concerning the kCap:
  1. I would, unless it is not possible, like to power it from a cheap bench power supply (0-30V, 0-5A). Having read the kCap-manual-r1.0.pdf, and assuming I need a 30J pulse, waiting 6 seconds between each use is reasonable to me (and I would let the ultracapacitor charge for a few minutes before use anyway, so it shouldn’t be an issue). I would use it setting the voltage to 8.1V and 5A current. Would it be possible/advisable ?
  2. Am I correct to say that if question 1 is possible, I will also need two extra M6 ring cable shoe for input (with in my case male banana plug connectors on the other side) that I would arrange (with in the M6 screws, washers and nuts) in I+/I- holes like the O+/O- are in the picture ?
  3. Do I need something else to make the whole “package” work ?

Thank you

Note : if this post doesn’t belong here, please point me to where I should post it and I will.
 
Did anybody tested the kWeld against a Sunkko 709A?
I'm looking forward to buying a spotwelder and like the possibility of the Sunkko devices to just run them off a socket. No need for a LiPo battery and just plug&play, comes with a soldering iron too. The prices are about the same for the Sunkko and the kWeld, so what's better?
 
Marv1337n said:
Did anybody tested the kWeld against a Sunkko 709A?
I'm looking forward to buying a spotwelder and like the possibility of the Sunkko devices to just run them off a socket. No need for a LiPo battery and just plug&play, comes with a soldering iron too. The prices are about the same for the Sunkko and the kWeld, so what's better?

If you want real spot welder you choose kweld or something similar. But only one is the best :wink: I have 1sunkko and would not recommend it. It's 220v version so it's better than the version for 110v but it can just barely weld 0.15mm nickel. It also trips my house breakers all the time so be aware if you have "new" kind of fuces that you just flip on and off. With older style fuse that is single use it worked better.

If you don't have a soldering iron just buy one hakko clone for 20 dollars.

I am not fan of lipos and had lead acid battery just gathering dust so now I am using it but it's real pain to carry around..

Ps I have sunkko welder on sale if anyone is interested :mrgreen:
 
I just dumped a functional sunkko to the electronics dump. :lol:

there is also a ardruino based spot welder for a bit less.
https://malectrics.eu/product/diy-arduino-battery-spot-welder-prebuilt-kit-v3/
 
eee291 said:
I just dumped a functional sunkko to the electronics dump. :lol:

there is also a ardruino based spot welder for a bit less.
https://malectrics.eu/product/diy-arduino-battery-spot-welder-prebuilt-kit-v3/

It's not about the price, the Sunkko is even more expensive than the kWeld. I just want something decent for under 200€.

ossivirt said:
Marv1337n said:
Did anybody tested the kWeld against a Sunkko 709A?
I'm looking forward to buying a spotwelder and like the possibility of the Sunkko devices to just run them off a socket. No need for a LiPo battery and just plug&play, comes with a soldering iron too. The prices are about the same for the Sunkko and the kWeld, so what's better?

If you want real spot welder you choose kweld or something similar. But only one is the best :wink: I have 1sunkko and would not recommend it. It's 220v version so it's better than the version for 110v but it can just barely weld 0.15mm nickel. It also trips my house breakers all the time so be aware if you have "new" kind of fuces that you just flip on and off. With older style fuse that is single use it worked better.

If you don't have a soldering iron just buy one hakko clone for 20 dollars.

I am not fan of lipos and had lead acid battery just gathering dust so now I am using it but it's real pain to carry around..

Ps I have sunkko welder on sale if anyone is interested :mrgreen:

Why is the Sunkko no real spot welder? I wasn't talking about the cheap 788H which is only like 130€. I'm talking about the 709A for 220€. (220v version)
 
Marv1337n said:
Why is the Sunkko no real spot welder? I wasn't talking about the cheap 788H which is only like 130€. I'm talking about the 709A for 220€. (220v version)
I meant that it's not really good spot welder compared to kweld and others that use lipos or similar setup. It's real spot welder but I would not recommend it to anyone unless they never need to weld anything else than very thin nickel plated steel strips and even then like you said at the same price you can get better. Only good thing about them is that you can use it by just plugging it to the wall..

However mine probably is the cheapest version possible so performance is most likely better on 709a.
 
crevettedragon said:
  1. I would, unless it is not possible, like to power it from a cheap bench power supply (0-30V, 0-5A). Having read the kCap-manual-r1.0.pdf, and assuming I need a 30J pulse, waiting 6 seconds between each use is reasonable to me (and I would let the ultracapacitor charge for a few minutes before use anyway, so it shouldn’t be an issue). I would use it setting the voltage to 8.1V and 5A current. Would it be possible/advisable ?
  2. Am I correct to say that if question 1 is possible, I will also need two extra M6 ring cable shoe for input (with in my case male banana plug connectors on the other side) that I would arrange (with in the M6 screws, washers and nuts) in I+/I- holes like the O+/O- are in the picture ?
  3. Do I need something else to make the whole “package” work ?
Your bench power supply can be used, but there's one possible caveat: some power supplies don't like being backfed into their output when they are turned off, and can get damaged in the worst case. Many don't have a problem, but you should check that.

kCap has two 6mm holes to mount ring cable lugs coming from the power supply, but soldering them directly is also possible. The kit doesn't include connecting material for the power supply side, but everything else is included to start welding after assembly.
 
Back
Top