🌠 Northern Light | Switchblade with Reverse-mounted Urethane Gear Drives

[jack.luis]

@rusins

That face when Raisins wipes out going 35mph

Look at this handsome mf

[rusins]

At home measured voltages of all the p-groups. Each is 3.88V. Wtf, why won’t it charge normally??? Charger outputs 50.5V, surely that’s within margin of error to still work?

I guess I’ll let this board collect dust until spring, not like I can ride it in the rain much anyway. Want to build a 12s4p battery for it too, save some weight compared to NESE and gain some range. With one of those duck PCBs

[BenjaminF]

@rusins

Each is 3.88V. Wtf, why won’t it charge normally???

Dang that’s really weird, I was sure the problem would be an unbalanced p-group causing the BMS to lock.

Did you confirm the balance wires are ordered correctly?

[rusins]

Did that back when it was assembled. Checked both with a voltmeter, and by hand.
Wondering what BMS I should use when I use this pack for my mountainboard. I guess an LTT smart one…

[rusins]

Hmm, I was thinking of just paying an EU based battery builder to build a pack for me since I’m busy with other boards, but none of the trusted EU builders have good example photos of their work to show off their skills. Most don’t even have a vendor thread, lol

If any EU battery builder is reading this, share your work! I’d be willing to spend ~450€ on a 12s4p P42A battery. But if you charge more, I’ll just do it myself…

[Blise518B]

Can recommend.

[EU] Custom Liion battery packs from Germany

Hey folks, I’m creating and updating this thread because I’ve built a ton of packs already. About me: I’m an electronics engineer based in east Germany and building boards and li-ion battery packs in my spare time. I use all the good stuff like quality cells from nkon.nl, pure nickel strips (tested in saltwater), insulator rings, fishpaper between cells with differet potential, high temp kapton tape and so on. Cells I use (*or can order if requested): 18650: Samsung 30q, 35e, Sony VTC6* 21…

[rusins]

I guess it’s fine if he stops welding directly in the middle of the negative terminal…

Edit: he shared some of his recent work, it’s good stuff Hired him to build the battery

[UFOskada]

@Acido

[rusins]

Same comment applies lol

Maybe I’m just spoiled by the pretty packs the US folk are making.

[Simeon]

Have you had a look at my recent IG posts?
I don’t update that forum post too often ^^

I don’t weld at the bottom center anymore since it was first discussed here (:

[City-Blade-101]

lol

[rusins]

I noticed one of my gear drives was loose

Well, I guess the grub screws that hold the gear drive to the hanger should have green threadlocker on them. Also I’ve lost a lot of the small bolts on the outside of the gear drive, because I only used blue threadlocker on them. I was scared to use red because I don’t want to melt the POM wheel gear when heating them up to unbolt. But maybe it’s safe? Dunno. Guess I have no choice.

Also the drives scraping the ground had ruined one of the bolt heads, so I had to completely drill through the bolt to disintegrate it

Also note that the plastic guards for 3d servisas gear drives love to jump over the bolts, so use some washers to make sure that doesn’t happen.

[tipsy]

@rusins

because I only used blue threadlocker on them.

Permatex Orange is your solution

[jack.luis]

Use red but only a small amount. Works for me.

[Savage1]

Great thread Raisins!

[rusins]

Thanks! @Simeon has just finished the final 12s4p battery for it too

Here is a photo album of it being built:

[39 new items · Album by Simeon P] 12s4p Rusins

Also shoutout to @Zach for selling me his FlexiBMS, it works!

I also have a green davega on the front now
Will take some sexy photos of the complete build once the battery arrives.

[Savage1]

ooh, thats nice! I got a switchblade coming next week, so this was a good read.

[janpom]

Wow, I thought I managed to build a decent battery but this makes me feel I still have a lot to learn.

[rusins]

@rusins

My charger also goes from solid green to alternating between green & red, but I don’t know what that means. Is it switching from constant current to constant voltage? (The stormcore button blinks if the charger is blinking, and at the same rate. From yellow to green. If I unplug the charger, it stays yellow. Hmm, in vesc tool it says the voltage is constantly switching between 47.7V and 49.3V. Is this some clever charging / monitoring strategy?

Yesterday my Bestech BMS started exhibiting the same issue. And I finally figured out what was wrong:

One of the p-groups instantly goes to full when charging. Took the cells out, 2 of them are definitely sus:

I wonder what made them go bad. Guess I’ll have to replace all 3.

I also noticed that there are nasty black marks on the tabs of my NESE modules. Should I be concerned @Agniusm ? They’re pesent on the other p-groups as well.

[Battery_Mooch]

@rusins

Should I be concerned @Agniusm ? They’re pesent on the other p-groups as well.

PMJI…IMO those marks indicate that the cells were bouncing in the holder, disconnecting/reconnecting and arcing each time.