Also interested about the top material. Is it nickel? Also where did you source your 0.25mm copper from? Can't find anything reasonably priced.
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Yamaha YZ450F
- Thread starter j bjork
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The top material is 0.10mm stainless steel. You want something that doesn't conduct electricity very well, nickel is not a good choice. I bought it on aliexpress in rolls 100 or 200mm wide.
It is really pushing the limit on the k-weld though, I need to have gloves to be able to weld more than 5 spots in a row because the probes get too hot to hold. Then I can do 10 spots.
That is probably why I have problems getting consistant welds, the resistance goes up in the wires etc.
Thicker wires and a fan cooling the internals on the k-weld might help.
It is really pushing the limit on the k-weld though, I need to have gloves to be able to weld more than 5 spots in a row because the probes get too hot to hold. Then I can do 10 spots.
That is probably why I have problems getting consistant welds, the resistance goes up in the wires etc.
Thicker wires and a fan cooling the internals on the k-weld might help.
Here is my plastic separator:
I'm not very worried that it will crack or something, even if it did I don't think it can go anywhere.
I asked for fiberglass, but they didn't have it. He suggested this instead, but I don't remember what kind of plastic is is
The folding of the two halves went well, now I just have to continue welding on the outsides..
I decided to do tree passes, so 6 spotwelds. As I'm not really confident in the quality of the welds, I go for quantity
I'm not very worried that it will crack or something, even if it did I don't think it can go anywhere.
I asked for fiberglass, but they didn't have it. He suggested this instead, but I don't remember what kind of plastic is is
The folding of the two halves went well, now I just have to continue welding on the outsides..
I decided to do tree passes, so 6 spotwelds. As I'm not really confident in the quality of the welds, I go for quantity
Thanks for the reply. I was wondering if it would be possible to make Wellgo-style plates myself by cutting 0.3 mm copper sheet with square cutouts for the cells, and then spot welding 0.15 mm pure nickel strips onto the square holes. This would make welding to the cells easier. The only part I’m unsure about is whether a kWeld can reliably weld 0.15 mm pure nickel to a 0.3 mm copper sheet.
Just tried spot welding 0.10mm Ni to 0.30mm Cu with my Awithz UF20 on gear 95. It did the weld fine but blew through both sides. Next I tried 0.15mm Ni to 0.30mm Cu but reduced power to gear 60 and it made beautiful welds. Try your KWeld. I think you will be pleasantly surprised. The challenge will be machining square holes in Cu if you do not have access to a CNC Laser Cutter.
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That’s great information, thank you for testing that. I really appreciate it. I’ll order some copper sheet and nickel strip and try it myself with the kWeld.
I think your Kweld is more powerful than my Awithz UF20B and may handle thicker material. I tried 0.15 Ni to 1.0mm Cu on gear 95 and it did not make good welds. I have a feeling mine will do 0.4 or even 0.5mm Cu but I don't have any to try.
If you do your layout with a sharp awl and straightedge, then a Dremel with cutoff wheels to cut out the squares will make the job DIY feasible. A bit of work but saves you a few hundred bucks from Wellgo.
edit: Just tried cutting a 11mm square hole in 0.3mm Cu sheet with a fiber reinforced cutoff wheel on a Dremel. The cut went slow, lot's of dust (I was wearing a covid mask), copper got hot, I stopped before cutting through the Cu. Didn't want to continue the experiment. Too messy, too much work on just one hole. Can't imagine having to do hundreds.
Find someone local with a CNC laser cutter see how much they charge.
Hole need not be square. Drilling a clean hole in copper sheet is tricky. Maybe a Brad point bit?
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Thank you for trying out! I'll try to figure something out for the holes but if nothing works, I have contacts to a local shop that could do it!
I was curios enough about Brad Point drill bits on copper I bought 2 of these. It works (0.3mm) and actually cuts instead of tearing and mangling the copper!
The other mangled hole was done with a Pilot point drill bit (result not acceptable IMO)
I used a Ryobi battery drill. On a drill press, results should be even better.
I had some 0.28mm pure nickel harvested from A123 LFP bus batteries and did some test welds with it:
Awithz UF20B spot welder on gear 90 made excellent welds of 0.28mm Ni to 18650 cell. Actually perforated it and let small amount of electrolyte out when I peeled the Ni off. Probably due to cell having been thinned from grinding old welds with Dremel stone a few times.
UF20B was not powerful enough to weld 0.28mm Ni to 0.3mm Cu. First with gear 90, then 99. Peeled off easily with my fingers.
Awithz UF20B spot welder on gear 90 made excellent welds of 0.28mm Ni to 18650 cell. Actually perforated it and let small amount of electrolyte out when I peeled the Ni off. Probably due to cell having been thinned from grinding old welds with Dremel stone a few times.
UF20B was not powerful enough to weld 0.28mm Ni to 0.3mm Cu. First with gear 90, then 99. Peeled off easily with my fingers.
Aren't you concerned about balance wires laying directly on cell insulation? I've always been shown/told to enclose cells themselves in Kapton tape, then lay the wires on thick double-sided foam tape. Keeps them in place and prevents them from chewing through to the cell casing from vibrations.
I don't expect it to be a problem, but yes, something in between is probably a good idea. I used thick double sided tape where I attached the cables to the cells, but not everywhere. Then I covered the entire middle section in self-adhesive foam that holds everything together, and protects the cells:
You can see a little of it under the bms in the picture.
the yellow is just protective paper over the glue on the double-sided foam I use on the sides.
I leave some of it on, because it sticks so much that it's almost impossible to get the battery apart otherwise.
Finishing up the lid.
Everything was glued together late last night, and tomorrow I'll be racing..
I was worried about fitment, so I tested it even though the glue hadn't cured yet.
Last weekend we where building the track for "stångebroslaget" (that I will be racing this weekend) and on Sunday we where able to testride. I planned to ride with my super soft rear tire on tubeliss, and I also rode on that on the test.
Guess what, got a flat:
This is what a pinch flat on a tire can look like
It also left a mark on the rim:
I think I will put the mousse in this tire instead, and run it anyway this weekend but with a mousse.
You can see a little of it under the bms in the picture.
the yellow is just protective paper over the glue on the double-sided foam I use on the sides.
I leave some of it on, because it sticks so much that it's almost impossible to get the battery apart otherwise.
Finishing up the lid.
Everything was glued together late last night, and tomorrow I'll be racing..
I was worried about fitment, so I tested it even though the glue hadn't cured yet.
Last weekend we where building the track for "stångebroslaget" (that I will be racing this weekend) and on Sunday we where able to testride. I planned to ride with my super soft rear tire on tubeliss, and I also rode on that on the test.
Guess what, got a flat:
This is what a pinch flat on a tire can look like
It also left a mark on the rim:
I think I will put the mousse in this tire instead, and run it anyway this weekend but with a mousse.
Nice work GL with the race! Will be interesting how your DIY busbars perform compared to the Wellgo's.
I don't think I will be able to tell if mine or wellgo is better. The difference would be very small and hard to measure I assume.
The race turned in to a mud party this year again, probably worse than last year. Well, I suppose it depends on who you ask.
The rain came earlier this year, so electric/veteran/(old)military and "exerciser" 50-59/60+ sure had it worse this year.
"Exerciser" 40-49 probably had it a little worse, but closest to the same as last year.
The younger age groups had a better race, and the race classes senior/junior/elite as it had started drying up.
It was very run down until then though.
Having a little rest under a military bike in the "startbend" (the first bend after the start where it narrows down to a few bikes wide)
Another rider turned in to me, so our handlebars hooked together and we went down. Some other riders crashed in to us I suppose, that is why that bike is over me. He wasn't the one that turned in to me.
Then the handlebars etc. was crooked, so I had to bend it back and was dead last.
There is maybe 1-2km from the start to the lap-timing, I was able to go from 106 to number 100 until then I think.
It had been raining a little during the week, but not too bad. But just after the race started, the sky opened
It was muddy water everywhere, I was muddy under the clothes. I had mud in my underwear..
The bike after Fridays race, covered in light mud. Too wet to stick in thick layers, but got in everywhere. The horn button got stuck on, I was able to get it off for a while sometimes, but the last 10min or something, and over the finish line it was on
The reverse was also stuck, but off.. And the on/off button as well, so I couldn't turn off the bike.
The thumb-brake also would stick, so I had to pull it back manually.
I was only able to do two laps, I was surprised and disappointed as I expected to do three.
I ended up 52 of 106 total I think in the group, so I passed over 50 other riders.
13 of 24 in the electric group, not great, but not a disaster I suppose.
The race turned in to a mud party this year again, probably worse than last year. Well, I suppose it depends on who you ask.
The rain came earlier this year, so electric/veteran/(old)military and "exerciser" 50-59/60+ sure had it worse this year.
"Exerciser" 40-49 probably had it a little worse, but closest to the same as last year.
The younger age groups had a better race, and the race classes senior/junior/elite as it had started drying up.
It was very run down until then though.
Having a little rest under a military bike in the "startbend" (the first bend after the start where it narrows down to a few bikes wide)
Another rider turned in to me, so our handlebars hooked together and we went down. Some other riders crashed in to us I suppose, that is why that bike is over me. He wasn't the one that turned in to me.
Then the handlebars etc. was crooked, so I had to bend it back and was dead last.
There is maybe 1-2km from the start to the lap-timing, I was able to go from 106 to number 100 until then I think.
It had been raining a little during the week, but not too bad. But just after the race started, the sky opened
It was muddy water everywhere, I was muddy under the clothes. I had mud in my underwear..
The bike after Fridays race, covered in light mud. Too wet to stick in thick layers, but got in everywhere. The horn button got stuck on, I was able to get it off for a while sometimes, but the last 10min or something, and over the finish line it was on
The reverse was also stuck, but off.. And the on/off button as well, so I couldn't turn off the bike.
The thumb-brake also would stick, so I had to pull it back manually.
I was only able to do two laps, I was surprised and disappointed as I expected to do three.
I ended up 52 of 106 total I think in the group, so I passed over 50 other riders.
13 of 24 in the electric group, not great, but not a disaster I suppose.
Thanks
It was a pretty tough weekend as I was also crew monitoring the other classes, and everything got delayed. I got home about 8 in the evening on Friday, washed the bike and changed numbers for Saturdays race.
Trying to everything working again with as little effort as possible.. Washing didn't solve it, but got all the buttons working with compressed air. Got the thumb brake working more or less.
Got to bed a little after 11 in the evening, a bit hard to sleep. Then up at 4 to get everything finished for the for Saturdays race, the first race in the morning at 8.
It started better than the other race, not involved in any start-crash..
I am number 143.
It was very tough, a big part of the track is gray mud that is really slippery and deep tracks. And some are this kind of watery mud that moves. It is strange when the rocky parts is where you can rest
I really didn't have the energy for this and got really exhausted quickly.
I did 2 laps in a little under 3 hours, and I wouldn't have done a third even if I was allowed to
It was enough for position 100, of about 220 I think.
On Saturday the mud sure was thick enough to stick.
It was a pretty tough weekend as I was also crew monitoring the other classes, and everything got delayed. I got home about 8 in the evening on Friday, washed the bike and changed numbers for Saturdays race.
Trying to everything working again with as little effort as possible.. Washing didn't solve it, but got all the buttons working with compressed air. Got the thumb brake working more or less.
Got to bed a little after 11 in the evening, a bit hard to sleep. Then up at 4 to get everything finished for the for Saturdays race, the first race in the morning at 8.
It started better than the other race, not involved in any start-crash..
I am number 143.
It was very tough, a big part of the track is gray mud that is really slippery and deep tracks. And some are this kind of watery mud that moves. It is strange when the rocky parts is where you can rest
I really didn't have the energy for this and got really exhausted quickly.
I did 2 laps in a little under 3 hours, and I wouldn't have done a third even if I was allowed to
It was enough for position 100, of about 220 I think.
On Saturday the mud sure was thick enough to stick.
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