Kweld spot welder

This battery (Turnigy Graphene Panther 6000mAh 3S 75C) is still out of scope and will be available maybe in September. Do you have any other recommended battery? I just need to build 2 battery packs, so 1 battery should be enough as a starting point, preferably from Europe.

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At the moment I can only recommend using smaller batteries and put them in parallel. Like two pieces of 3000mAh 3S 75C.

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I tinned the end before stripping and that kept the bundle together fairly well. I think the joint looks good. I did get some solder down the back of the xt90 connection tho (last pic)

. Is that a big deal? I do have a desoldering braid if need be…

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as long as you have a solid connection it doesn’t have to be pretty.

Looks kinda cold to me but that’s a little expected with all that copper succing up the heat.

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May just be the shitty pic. IRL its pretty shiny. Lemme try w a flash…

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it does look a little cold, but it might be fine.

Did you tin the cup as well? I tin the wire, then set up the helping hands, tin the cup, them join while the cup is still hot. 8awg is hard to starting with clean tools and adding some flux are required.

Solder starts to look peaky, stiff, and frosty when it begins to oxidize. I try to get my solder points to look shiny and smooth as possible. The longer you apply heat the more oxidation will build.

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Yes, I applied flux to both the cup and wire, then tinned the cup. I def had the iron on longer than I would’ve liked- hence my struggles w soldering this big ass wire. If it is indeed a cold joint and I decide to run it, what should I look for with the kweld to let me know its a bad connection?

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it would heat up and you could feel it with your fingers

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Thx fellas. Appreciate the help.

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yeah, or fall off. basically, if the connection is weak the current will bottleneck there and show its love for you by warming up and glowing with joy

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Ya second joint looks much the same. Think I might need a higher wattage iron. 70 isn’t cutting it. Think I might just pick up a big ol’ 100 or 150. Just annoying to have to shell out for a bigger iron that I’ll almost never use :confused:

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I have a 60w Weller and it’s just enough if I work quick and clean. Once the joint starts going peaky on me the iron does not have enough heat to power through and I have to start again clean (I like this, kind of?)
Clean is the key for me, any of that shmeg on the work or the soldering tip and the joint is doomed. I like to have everything in position, bright, shiny, clean and fluxed before I start.

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One thing i’ve read and is the next thing I’m trying to put into practice for these welds to large copper is that the thermal mass of the tip is important. helps compete with the thermal mass of the thing you’re welding too. so make sure you’re using a bigger tip.

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Readers of this thread may find this interesting:

doesn’t work with kweld yet, but he’s thinking about it.

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I picked this up for £32.90 there are other sellers selling the same thing, if price is imperative and you don;t plan on crimping anything else ever again(unlikely) you can get a manual one for as little as £10 probably

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Did u crimp the 8awg onto the xt90? Didn’t even know that was possible…

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Nope the probes require crimping to lugs to secure them to the pcb, also the probes themselves can be crimped on to probe leads

Edit: you may have paid for assembled leads in which case no crimping tool required!

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I did indeed good sir.

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Who has the BOM for the kweld…

I had my power supply i use set to 55 volts and forgot my kweld was plugged in

The buck converter inside? Or something dc dc related made a weird ass noise and now the kweld is inconsistent and does weird shit.

Not to self… Don’t be stupid

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Can you tell me more of the module’s behavior now? Does the LCD turn on, do you see messages? You can also measure the voltage across the large electrolytic cap, that should be 10V. Try running through CAL with a bench supply and record all data that you get.

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