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‘The Wingtip’ | 10-pound commuter

Well, the target is in the topic.

Currently, this is only thoughts and plans but I think that put my ideas here is better than spamming in every thread with my questions.

So, what we are dealing with?
FG deck, single drive with 83mm wheels and small swapable battery.

Last one is questionable. I’ve already asked folks in the battery builders club about 10s1p battery of vtc5a cells. They are capeable of pushing up to 35A, that is ideal for a tiny battery. But it is if not considering voltage sag. Unfortunately, even at 20A, sag reaches impressive .4v / cell. Actually, burning 120+W of energy is not that cool at all.

On the other side, according to this sheet made by @professor_shartis this config is capable to climb me at 10% hill at 15/36 gear ratio at 22 battery amps:
peak_loaded_velocity_and_gear_ratio.xlsx (6.2 KB)

Anyway, I would definitely be glad to hear your thoughts not only about the battery but also about the ways to make this board as light as possible

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Have you thought about using lipos?

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Small boards need small motors, you can save a lot of weight by using components of the same power caliber

I ran a 10s1p 40T battery with a 5065 motor and 76mm wheels, it works pretty well and I think it was exactly 12 lbs with a 36" deck

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Wanna forget ‘em.

Actually, not that bad idea at all, but not as nearly as compact as 18650

Just a little bit info about components:

Motor

140kv 5065 noname, but pretty quality one:


(left one, sensored)
Weight: 450g

Esc

Maytech 4.12, works fine for 2 years, already moved me around more than 200 km

Weight: 120g

Wheels&Trucks

Well, these are battle-scared, gonna replace them with 4 new orange ones.

Trucks are going to be repainted too.

Weight: 1900g

Gearing

Planning on 15/36 htd5m, since it will give me max torque without significant slip

Assuming 2nd gear and belt,
Weight: 200g

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Motor mount
Edit: Not decided yet, but possibly like this 3d printed one. Choice depends on the temperature of the motor. If it is not going to warm up that much, thin plastic mount would work great, such as this one:


But in all-metal version.

Weight: roughly 200g

3d printed mount is first row ticket to ER.
Please don’t cheap out on essentials.

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Actually i do not trust default motor plate design. Yes, it is robust, but handling belt tension (especially with low teeth motor pulleys) using 4 bolts perpendicular to the tension direction is the nightmare of the engineer.

But your reply makes me thinking about creating the same design as my 3dp, but full-metal. It would be nice, actually

What is a “FG deck”? Fibre glass?

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Maybe a carbon fiber motor mount that’s epoxied to the truck hanger would be the lightest way I can think to do it, that would be reliable.

Like half of an enertion motor mount without the metal bits.

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Is a belt drive generally lighter than a hub drive?

Edit: I am looking for hub motors that weigh less than 5 kg and are compatible with cloud wheels or all terrain wheels (something not urethane). However, that seems not possible, I have learned. So I will have to use TB DD; however that thing is very heavy and I want to build a light weight small commuter board too - comparable to the commercial backfire mini.

I don’t believe so because of the pulleys and mount and wheel innards, but I would still prefer a satellite motor configuration anyway. If you used aluminum pulleys and even drilled some holes in them for weight reduction I think you could get close except have a lot more performance.

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  1. It is not.
  2. hubs cannot be normally used in single drive => +1 esc, bigger enclosure, more shit to happen.
  3. deck is fiberglass, so it is rigid. How about 2mm thane on the rigid deck?
  4. hubs suck generally
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Hubs are best for going clandestine in countries where eskate is illegal, e.g. Germany etc. Single belt drive has no torque for going uphill.

Speaking about motor mount, I think that idler & fixed motor position on the plate will work the best for me just because of two factors:

  1. Only 1 bolt to adjust the tension.
  2. Idler will help with belt slip bc 15t is still not a lot.

Well, I would be really happy, if you would find a hill in Moscow that is steeper than 10%. Yes, I can encounter some inclines, but generally not significant.

And yes, Moscow is in Russia, so esk8ing is as legal as being a pedestrian. So hubs still suck in my country :sunglasses:

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This is definitely not true as stated — a single TB6380 motor on a single drive with a good ESC can haul ass up some hills. (and I’m a fat guy) It’s not the lightest weight thing though, however it’s much lighter than a dual drive.

In context of lightweight and only using a single 5065, yeah hills aren’t going to be its specialty, but it will be able to traverse them. Just not with tons of power. I’ve gone home on a single 5065 many times when there was a failure or other problem, and it will move you around just fine, and even up hills. It just feels very sluggish going up hills and when slamming the brakes hard.

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I would use a lipo pack. Easy to swap out and a high c rate .

Interesting. Probably you have much more experience with single belt drive setups than I do … I only tried a 110 KV 6384[sic!] 6364 motor from Trampa (advertised as amazing hill climber!") on an Urban Carver board with 7 inch tyres, I think, and a VESC 6+ - that left me very disillusioned, since I could hardly go uphill at all.

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10 pound (4540g) is really light and going to be difficult to acheive.

However, I would not skimp on certain things, even if you puts you past the 10lb mark.

I would use high quality cells, maybe a 10S1P of Molicel P42A, even if heavier.
I would also use a satellite single motor configuration as discussed above, even if heavier.

…despite both of those being heavier than the alternatives… …because the longevity and performance improvements will be worth it, imho.

The things I would try to make as light as possible are things like the deck, the wheels, drill holes in anything you can, like pulleys etc, use smaller gauge wire like 14AWG or even 16AWG, no motor sensors (physically remove them), no connectors – solder everything together, basically have no parts that aren’t necessary to make it functional. You could also make the “deck” and the “enclosure” the same piece of custom fiberglass…

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