Def interested, could you make one for kweld with existing electrodes?
I don’t own a Kweld yet, but maybe. The fuse welder design is too different to try to incorporate the stock Kweld electrodes into, plus they are enormous. I have an idea in my head for a “standard” two electrode design using springs on each side as well. In theory it would distribute the pressure between the electrodes, making it easier for newbies to weld while getting the feel for how much pressure to use.
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Maybe you could make your design so that it just bolts straight onto the default bolts. That way, if the user wanted to switch, they could have their default electrodes and then your tool.
You’d have to see how the kWeld works though because there is a calibration sequence and the cable lengths are very important
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My plan for the Kweld is a standalone pen with active cooling and swap able tips. Sizing the leads for the default bolts would be easy enough, but I’ll also have to beef up the unit to handle the power the Kweld can deliver. The spot welder I’m building this for is a cordless, handheld device called the Nano. It’s great you can throw it in a backpack or a drawer, but it doesn’t compare to the output of a desktop welder.
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Sounds pretty neat - the kWeld isn’t actually that big either but yes, we are talking 1k amps haha
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Preeety cool, I toyed with this in a manual fashion but it was too tricky to get right using silver coated copper wire 0.5mm
Seems like you designed the tool for the job, nice one!
I found cell level fusing with solder a right pain in the hole time-wise, would certainly be interested
Have Kweld as do most of the battery people who like to get the nice tools
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Watching this thread!
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This is GREAT! Wellcome!
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[quote=“magharees, post:29, topic:35637”]
Preeety cool, I toyed with this in a manual fashion but it was too tricky to get right using silver coated copper wire 0.5mm
[/quote] The flat electrode really helps with that, as well as the pressure from the spring. I’ve done 34awg all the way up to 26awg with my prototypes. Trying to solder cell level fusing was what got me started on the project!
Thanks everyone for the warm welcome. Here’s the latest prototype with active cooling, a stronger spring, and a few changes to make it easier to assemble. So far it’s passed all my tests, and I’ll be posting a video of it in action on my Youtube channel soon.
Forgive the messy 3D print, I was in a hurry
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That makes sense cheers!
Update on the fuse welder: Many changes and tweaks in V1.3.4. Just tested on 26awg and 28awg tinned copper wire. Welds are strong and broke at ~800-900g. Getting close to something I’d be willing to send out to testers. Here’s a quick video: https://www.youtube.com/watch?v=7k3ik1p4i3M
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I think it needs to be wire from each cell to a parallel bus bar. Cells are 10-30 amps each while P groups can exceed 200
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Here’s what I hope is the FINAL version of the fuse wire welder for the Nano cordless spot welder. Sending out a few prototypes for usability and stress testing today. I’ve successfully tested with up to 26AWG fuse wire which is roughly equivalent to a 20A fuse. I’m not sure if that makes it any more useful to high power applications such as electric skateboards or not.
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Looks great man, if you’re looking for anymore testers, or putting together an initial order list, let me know. I have thousands of new and surplus cells, experienced building packs for various applications, including numerous ones for my off-grid property, with many larger ones in the making right now.
Also, a machinist with a fully equipped manual machine shop and fab equipment if you need help with anything along those lines.
I’d definitely be interested in cell level fusing for my esk8 packs, as I’m of the mindset to not have a built in BMS handling current control for various reasons, we’ve discussed in length on other threads here. I’ve got plenty of the nickel fuse that BHU sold but it’s limited in current and configuration characteristics that wont work for many of the cells we use.
Also have some of those model 3 cells en route.
Anyway, awesome work!
Definitely interested in testers, especially in applications I’m unfamiliar with. My use case is in powerwalls not skateboards. The tip does require a small amount of machining I’d be interesting it talking to someone about, my skills are lacking in that area as well.
Regarding lack of a BMS my intent here was more of an added protection against having a cell with a dead short. I’m not sure how limiting the current with fuses would work but you’d lose a lot of power to excess heat. I had looked at the BHU fuse sheets and for my application (Planned ~20k cells) it wasn’t a reasonable option hence the birth of this prototype.
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Yeah sorry if I didn’t explain that well, wouldn’t be using the BMS for current control, our ESC controllers already handle that, which is why I don’t believe in adding a BMS in front of that when we’re talking a couple hundred amps.
I still use BMS for balancing and cell maintenance. Would like CLF for exactly it’s intended use, dead short, or some instance where a cell decides to dump for whatever reason.
As to the machining aspects yeah man, hit me up, I’ll PM you my number.
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@surfnacho and some others on here.
I’d love to test it with the Kweld, and use the batteries for charge and ride systems.
I’m getting model 3 cells too!
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Javand, that makes a lot more sense! I’ll be in contact.
Fosterqc, PM me your info and I’ll send you one to test. Without active cooling and due to its small size it will likely heat up pretty quick.
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I never PMed you, but would love to test! I can help you design and print some cases as I got a resin printer now.
anyone interested in update?