‘The Wingtip’ | 10-pound commuter

@LuuktH this only works on some bms’s.

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And moreover, I’m not a fan of pre-built bms.

Passive balancer + charge port + cccv charger serve any needs in battery charging.

FTFY :smirk:

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BMS

So here we go


Gonna feed this topic with some pcb etching photos

Update:
Finally, I have successfully soldered 1 balancer sub-circuit out of 6 and tested it. It reached impressive balancing current of 200mA w/o any problems and I’m sure it’s not the limit.
More importantly, this thing starts balancing before cell reaches 4.2 volts. Keeping that in mind you can use this for a huge packs that do not handle their voltages well enough.
Definitely going to share more details later

Update 2:

I failed to solder so many dense smd components using soldering iron


So, why not reroute the pcb to make this thing more soldering-friendly?

I’m not going to etch this thing right now, until the motherboard project is complete, because who knows, I still have spare 10x40 mm space left that I can use to place voltage dividers for each cell to monitor them. Keep in touch for update 3 :smiley:

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Battery

So, I ended up with using lipos :smiley:

This battery is made of two hrb 3s 5000mAh lipos.
totals: 6s 5Ah, 111Wh in total, the same old 750g

I attached epcos 100k thermistor (from my fried ender 3 :man_facepalming:) to the most suspicious cell. Not only because battery temperature is important, but also because I always wanted to :slight_smile:

Next, I placed foam between packs and covered them with electrical tape. I know that I would better use shrink but it’s kinda hard to find it here and waiting for this thing from China is kinda bruh to my taste.
Orange wires are thermistor, balance wires remained as is:


The only thing left to do is to solder xt60 to the output

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:heart: :sunglasses:

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Heat shrink enclosure?

mind_blowing

But more importantly, this leads me to thinking about sandwiching all your electronics in between two pieces of foam, heatshrinking around the deck and everything, and laying fiberglass on the heatshrink… for a form-fitting fiberglass enclosure… then removing the heatshrink and bolting it to the deck.

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This…sounds doable. Holy shit you may be on to something

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Here an example of a <10lb board

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reminds me of @whitepony somehow :smiling_face_with_three_hearts:

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Honestly, i think this log thread is almost an archive of recommendations at this moment

This thread was dedicated to “U1: Wingtip”
But during the work on parts, I’ve scraped almost every idea i had at the beginning and want to start all over again in 2021, with “U2: Winglet” as it was suggested

I think, that is the reason of my versioning problem explained here:
https://forum.esk8.news/t/the-bitching-thread-bitch-about-random-shit-get-it-all-off-your-chest/8694/2233?u=kntzn

So, stay tuned for new thread in the nearest future, I have a lot of interesting stuff to be done in January:
Upgrading the Ender



Going from avr to arm

And other not-esk8-related DIY

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If this was in europe id have bought it in a heartbeat.

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Just weighed my coyote build, 8.5lbs! I’ll post pics tomorrow. Happy new year.

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Damn it, Must’ve been a fluke on the kitchen scale, bathroom scale says 12 pounds.

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3d printed mount ?
With what filament ? How does it hold up ?

Haven’t ridden it yet, just finished assembling, I’ll let you know. This mount is a prototype; caliber 1 trucks. It’s petg, all bottom layers, 0 infill pattern, only worried about motor heat at this point. I think I’ll print a cooling fan, found a post on endless sphere where they claimed the fan cooled the motor 20*c

Also need to reprint the bottom cover piece, it’s short a few mm.

Be careful with it, petg might not be strong enough to resist the vibrations

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I’ve experimented a lot with 3d printed mounts and in my experience single mount just doesn’t work, the plastic does flex a lot resulting in belt skipping. What works is a dual motor configuration with the two mounts connected with a threaded rod or something, that way it is rigid enough. However, the motor heat is still a problem. It doesn’t necessarily melt the mounts, but the plastic mount doesn’t dissipate the heat like aluminium, resulting in overheating motors really quick.

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