55A for 10awg according to this chart.
Maybe I get something wrong.
That can be as well. I didn’t find the fusing chart yet.
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i don’t if this is the case now but battle hardening can help if you have “clicking” noises. these can be caused my the moving windings under inductive field forces. that’s why you don’t see any damages nor issues moving the motor by hand.
the endless sphere table is spot on. I tested these values againt real live testing with high current injection tool.
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Good point, gonna think about battle hardening. I have a slightly preference for just mounting the spare SK8 so I have more time for inspecting plus I can ride. Also the clicking motor was strange from beginning. There was a bit play sideways, the others don’t have this. I put shim spacers between motor bearing and helical so the play was gone. It’s a miracle why the movement came back and even got worse.
Nice! What was the length of the strips?
Meanwhile I soldered the adapter to test the BMS
Well, 12s pack has 44.4V
Let’s see what the BMS output voltage is… 
Damn it, all connections are correct, also measured each pin of the balance connector.
Spent too much time to wire this up for nothing! Have to rethink BMS options (2 left) and whole wiring of the Li-ion. One step forward, 2 steps back.
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I can imagine sideway play can increase over time in your case. Disadvantage of helical gears is they produce axial thrust force. Normally you need to have thrust bearing to absorb the force. Herringbone gears would solve this but more complex to produce. Unfortunately helical gears are actually not proven yet for esk8 on the long run. Maybe this is not the case but it should be considered as a possible cause.
only tested short piece of nickel. More length only causes voltage drop. Heat is our enemy, length is too short for significant voltage drop
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But how? The only reason I can think about would be crushed or damaged bearings with play inside. Between motor bearing and glued gear are washers with zero gap. The can and shaft had play sideways when the motor was brand new but after gluing the gear it was gone but came back even worse.
I used them for about 500-600km so far but see no problems. I need to ride more for long term experience. Good point with the bearings. Probably they need to be replaced earlier than with straight gears. I will research if there are thrust bearings in the correct size available, good hint!
It would be interesting to know how much pressure or which force actually is on the motor bearing due to helicals. Radial bearings can take axial forces if they are not too big.
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I was time to test the kweld and have a spot weld party 
First tests with a single weld with 0.2mm thick nickel strip
after removing with pliers
Now testing 3 welds each strip with 30-50 Joule.
Removing the strips is not easy at all with 3 welds, especially 40 and 50 Joule as you can see.
It was time to test 0.3mm nickel strip with 50-100 Joule. The welds are so strong that it is impossible to remove them with pliers, only the steel blade breaks apart 
After a while we realized that all the black marks on the backside of the steel blades come from the burnt wood which is laying underneath 
Then the idea, I have a solder mat where you can put the soldering iron directly on it without any damage. So perfect to withstand the heat of the spot welds. Well… not really
Instead of black marks there are now white marks on the backside of the blade 
However this spot welder does a great job and with the nano-tech 65C-130C lipo it welds with 1300A 
During testing the cables and lipo stayed cool with 0.2mm nickel strip. When welding 0.3mm nickel with higher settings both got warm. The tips don’t get hot because of their massive size. I’m curious if they get warm when welding a whole pack (or half).
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can confirm that once you get into the flow of welding tabs those probes will start to heat up. because you are focused it will start to get uncomfortable to hold but you will think “its ok i will keep going till the end of this row”. By the end of the row they will be VERY HOT.
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I think bearings should be damaged then.
Would be nice if you can find the mechanical failure.
Would the geardrive in general not put extra stress on your motors as well by heavy abuse. Belt drive dampens the vibrations transfered from the wheel.
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Nice work with the testing of the spotwelder
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@rich & @ducktaperules, and anyone else using the kWeld system. Would you mind outlining the settings you use on standard 8 x .15 nickel? My brother just bought one of these and is trying to get some info before it’s delivered.
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Found it 
First massive failure is this hole
Now I know why I had metal chips inside the can. You can look through the bell WTF!
Second I finally found some loose windings which I can move.
But now another disappointing story. I prepared the new SK8 motor for the helical including cutting the shaft. Today before work I glued the gear to the shaft with Loctite 638 and wanted to do it very accurate. I applied and spread it on the inside of the gear and on the shaft. Then I made a ring around the tip of the shaft. Very slow and by turning I slided the gear on the shaft for maximum strength. Just before finishing I wanted to soak the tiny bit retaining compound at the end with kitchen roll paper. That’s the end of the story. I realized the retaining compound got monster sticky already after about 3 minutes and I couldn’t move the gear anymore. Even with a pulley remover it was impossible. Also my small blow torch didn’t help. Daaaaaaaamn 
One step forward, two steps back, that was a bad moment. Next step is to buy a proper blow torch for removing the gear without cooking it.
I have 0.2mm and 0.3mm nickel strips only but this is a suggestion from the manual:
From the testing of 0.2mm nickel 40 Joule is enough IMO, even 30 would work. So I guess for 0.15mm nickel it’s maybe 25-35 Joule. Best is to test it first. This values are for nickel on steel. Nickel on nickel need higher values.
Just a short explanation about Joule
This is the kweld manual and here the assembly manual if your brother didn’t download them already.
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Good info, thank you.
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Forgot to post the pic when testing the fishpaper, this is after 1 weld.
This is the bottom side
There is no hole but it’s also 1 weld only and I would feel safer with at least 2 layers. For example if someone welds nickel tabs (with pre-soldered balance wire) in between 2 cells then there are fishpaper rings underneath. Or better avoid doing this .
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I’ve used a heat gun on 420 degrees Celsius a couple of times now and it worked great. Took some time but got the job done. Doesn’t burn the gear either.
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I use always a cheap weed burner of 5 euros. Works perfect. Heat the pulley for 30 seconde and it come off without any problem.
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This is the new blow torch compared to the old 
What an epic flame, it took 30-45 seconds until it started to smoke and smell and I could remove the gear. With the small one it took several minutes.
After a bit sanding and cleaning I finally glued the gear on the shaft and this time like it should be. If you stay within 1-2 minutes then it’s no problem.
True. This time I didn’t burn anything because I heated the shaft only.
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My little brother has a kweld system coming, it looks pretty great.
My malectrucs is dead 
Soldered sensor extensions and finished wiring plus added new foil on the motors.
Finally it was time to put everything together, or not?
It seems I didn’t hail skatan enough because the new SK8 has heavy resistance when spinning. I realized it when adjusting the backlash of the helicals. Feels like a small internal short. Just to be sure I removed the wiring but no bullet had contact. When spinning the can only the difference is smaller but the resistance is heavy when spinning the gears 
Instantly I had to take the Urban Burro and go for a ride to forget about this disaster. I had a lot of fun and got dirty on all terrain and fell off a couple of times because of no bindings. Then the dirt path was wet and while turning the rear of the board slipped away so one foot left the board, tried to balance with the rear foot on the ground. That didn’t work and ended in eating the bush and dirt
But nothing happened beside dirty clothes, just a funny moment.
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Damn that’s the number one reason why I’ve always been worried about putting permanent threadlockers on any of my bolts 
If you had a spare stator drive shaft and helical motor pulley, would you have been able to remove the shaft/helical gear assembly and just replace it with a new set?
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