Noob question thread! 2020_Summer

Yeah… it’s true, I love it :man_shrugging:

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Don’t use krapton tape to insulate it’s a fire waiting to happen. Use more barley paper between both half’s of the battery.

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I bought a board and was able to get about 7 miles out of it before it decided not to charge any more. My first thought was I might have let the batteries get to low. So I put it on a treadmill to use regenerative breaking to charge it to the point the block charger would work again. That didn’t work. When testing the cells non of them are out of balance so I dont think its the battery, and because the ESC will kick on and connect when its on the treadmill I don’t think that’s what is broken either. Leaving me to believe its the BMS that’s the problem.

Now after writing this I just researched the nominal voltage of the cells which is 3.6 - 3.7v and my p-groups are all at 3.53 - 3.55v making me now think I should get a bench power supply that can charge them.

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twist 'em.

If think 12awg fits just perfectly with the mr60

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Yes, but use 12AWG

They will fit. Strip more than you need. Twist them. Tin them. Cut off the end leaving a nice small twisted part. Plug MR60 male into female. Tin MR60 pins. Heat and stick them together.

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Thanks for the tips.
It’s not that I cannot do a good job with it, it’s just a bit too close. Sometimes I put barley paper in between the bullets while I’m soldering so it doesn’t short with the next bullet.

I’d try changing the BMS then. If you’ve verified all P-groups are 3.53 - 3.55V with a multimeter (DON’T accidentally short anything out) then maybe try connecting the charger directly to B+ and B- for a few moments to see if it kicks to red. If so, I’d stop charging and order a BMS. Don’t leave that connected for an extended period of time unless you are constantly checking every P-group with a multimeter. Better to just not do it.

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Cool noted

Polyimide (aka Kapton :tm:) tape has its uses in battery building, but vibration resistance isn’t one of them. Fishpaper or barley paper is better for vibration resistance. Often the two are used in combination. Polyimide tape is really good at heat resistance, and the reason it was developed for the spacecraft industry.

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Has anyone run 18s on the Ubox I see it’s rated for 75V with peak of 80V.

Channel trucks are similar to the lonestar you tried last week (i mean, those are actually some really good channel trucks). You may have noticed that while the board is huge, tyres are only 7.5 inches, quite small. There is another guy local with another lonestar that really likes to drift with his, but he went a step further and even tried 6 inch wheels on.

Don’t shoot straight off to huge wheels, they are not the fix to everything, and keep in mind tkp’s come straight off original skateboard geometry, which doesn’t compare to the rkp’s stability

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How does this charge port go back together!?! Took it apart to solder it and it fell apart as I did it so I couldn’t remember how the plug attached to the handle.

@BenjaminF @DerelictRobot @anyone else who knows about this thing

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Cap in the middle goes over grommet side (with cable through already), silver thingy goes on other side of grommet, rubber washer on top and big sleeve thingy pops in last. I’ve never seen this irl so i’m only sure that cable goes through middle nut and top gland to be soldered on silver thing

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Well lads, problems are still coming in. Guess i have to change my title again.

Remember about the crackling sound i had with the neoboxes? I fixed that after flashing Ack FW and 5.02 again.

Now with my unity i’m having the exact same issue on 5.02.

I can spin them up until 94.7% but as soon as i continue to increase the throttle it starts the sound again.

E: this did not happen on the unityFW 23.46 (or whatever the latest one is)

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Wow, that sucks and I don’t know what’s causing it. :frowning:

But I know what I’d do. :slight_smile: Set the “Maximum Duty Cycle” to 94%, loudly exclaim “FUCK IT” while you click “Write Motor Settings” and live happily ever after.

I mean, it’s a, what, 1.05% top speed decrease? Who FOCing cares at that point

…unless then it starts happening at 93.7% because it’s an actual firmware bug…

… in which case your findings could actually help the developers find it

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does exactly that. I’ve set it to 93% at it also starts to crackle

E: even 87%, so no matter what.

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I’ll try flashing unityfw and then vesc fw again and hope it also gets fixed like with the ACK.

Might be that your controller overshoots the maximum duty cycle and it actually reads about 2-3% lower. Does it behave the same way under load?

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i haven’t tested it under load yet. I also don’t want to in this state if i’m being honest.

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this is how the graph looks like. The big red and Blue spikes are when the crackling occurs.