Personal Cruiser, Two 6356, Two VESC, 6x2 pneumatic tire - CarveBoardUSA Trucks and Deck - Stick Restoration

[Morgan]

Two weeks ago (as of Oct 2018) I came across two motors fresh in their box and I had always thought I would use them for an airplane or two (these motors are sold for RC airplanes). Then it popped into my head that they would be the perfect electric skateboard motors!!!

Then it happened… I found myself obsessed with building the ultimate commuter board and addicted to this process of building an electric skateboard. I commute via airplane (LongEZ) weekly to San Fransisco and have been seriously considering buying an eboard for getting around SF while I’m there. The only problem was I felt like the small wheels on the commercial boards would be problematic on the streets of SF. Could I build a better board? During my initial research, I found this forum and realized people were doing this successfully and often. Great community here! I’ve taken the eSk8 crash course over the last week. Now its time to BUILD!.

Objective: Build a fast and robust eboard for commuting that can handle tough urban and rural terrain, use the CarveBoard Stick chassis as a starting point. The CarveBoard Stick has been a GREAT skateboard!!!, iv ridden it hard for 10 years and now its time for a refurb and electrify it.

Requirements:

1. Waterproof
2. Not get tripped up on rocks, cracks, uneven pavement.
3. Off-road capable but not a strong design point
4. Stable at speed 30-40mph
5. Reliable electronics
6. Tough drive system
7. Cost under $900 (not including parts I already have)
8. Easy to use i.e. easy charging, operation, on/off,
9. Fits in my LongEZ

Performance:

Specs as of Oct 2018 Two - Monster Power Series - 6356 kv295 Trucks - CarveBoardUSA - Stick Deck - CarveBoardUSA - Stick Wheels - 6x2 pneumatic Drive - Chain 5:1 (11T - 55T) ESC - Flipsky VESC Battery - 6 2S 6200mAh 50C LiPo Controller - XCSOURCE 2.4GHz Radio Motor Mount - Custom Carbon Fiber Battery Tray - Custom Carbon Fiber BMS - 48V 12S 80A Lithium Battery BMS

Phase I - Buy a bunch of parts to get the project going

(picture)

Amazon Order: 4x 6x2 pneumatic tires Trivent Electric Skateboard Power Switch 6x OVONIC 2S 7.4V 6200mAh 50C Lipo Battery 48V Battery Meter Flipsky DIY Electric Skateboard ESC Based On VESC XCSOURCE 2.4GHz Radio Transmitter Remote Controller BNTECHGO 12 Gauge Silicone Wire Finware 10 Pair XT60 XT-60 Male Female Bullet Connectors #25 Chain Drive Sprocket 55 Teeth

Monster Scooter Parts order: #25 Motor Sprocket - 11 Tooth #25 Chain Sprocket 3 Holes and 55 Teeth #25 Chain Sprocket - 55 Tooth #25 Open Loop Chain - 3 Feet

Phase II - Design layout and motor mounts

Motor Placement:

I did some CAD to help with the motor mount design. If anyone would find some of these models useful let me know and ill find a way to upload them.

Layout: My plan is to use3M Scotch 5952 VHB Tape to stick all the components down including batteries. With the BMS and batteries attached to the deck surface and the VESCs + antispark/switch mounted above either on the battery tray or spaced above the BMS (stacked). Question: Do I need an antispark/on/off switch if I have a BMS?

I’m very open to any opinions anyone may have about this board. Please let me know if you see any possible issues or opportunities to improve.

Some questions I have at this point: My motor seems to be on the high side of kv from what I have seen on most builds. Does high kv negatively affect low-end performance? My motor: 6356 kv295

I read that the VESCs can have wired breaking issues at high speed. One of my missions is to do some re-gen downhill runs. What would the best ESC be for that? and will the VESCs be ok?

Next: CAD and CNC motor mounts, mount sprockets to wheels, and order BMS.

[pat.speed]

Ok so you have a little issue. The Kv is a bit high. Usually for 10s batteries you want below 200kv. But luckily you can limit the erpm of the vesc to stop it from cooking itself. If the vesc setting there is some info about the erpm, I would set it to 58k and -58k that means that when it reaches the speed it will start to back off so it doesn’t fry.

The other issue with high kv motors is the torque output. If possible I would try to increase the gear ratio a bit more to maybe 5.5:1 or 6:1 just to have lots of extra torque. Maybe swapping the motor sprocket down to a 10t would be good, although you might as well try it how it is first before changing the parts

Apart from all that the build looks pretty cool

[Jake2k17]

Yeah almost 300kv…fuck

[pat.speed]

It’s fine mate… peeps used to use 280kv 5055s, back in the day they were the shit lol

[Jmding]

If I were building a high power board, I would use motors in the 250 to 300 kv range, pair it with fsesc6.6 escs, and use the smallest motor pulley available and the largest wheel pulley that doesn’t scrape the ground. At 12s 300 kv, that puts you around 35 mph top speed. Since the high kv motors have fewer turns and lower winding resistance, they will heat up less, can handle higher currents, and therefore can ultimately be more torquey after gearing. That said, it’s still better to use lower Kv motors if you don’t want the higher top speed.

[Morgan]

I’m trying to go to the lowest gearing I can find/fit. Right now im at 5:1 with 11t to 55t gearing. Can’t imagine I can get smaller on a 10mm shaft, so I’m looking for a 55+ sprocket that I don’t need to do a lot of machining on. Good to know about the rpm tuning, thanks!

[pat.speed]

ahh yeah didn’t see you were using 10mm shafts. 11t is probs the smallest without drilling the hole our yourself. Anyway I’d see how you go, I’m sure it will work.

[Jmding]

Yeah that’s challenging. If that’s the most extreme gearing you can realistically achieve, you probably want to go lower in Kv

[Morgan]

Well we’ll give it a go. May need to get new motors in the end.

[Morgan]

Motor Mount CAD: I located the motors and framed out a motor mount that could be 2d CNC routed out of 7mm carbon plate. I incorporated a plate under the motors to act as protection and stiffen the frame. Two aluminum rods will be like a rear bumper and also add stiffness. This board turns deep so making sure there was clearance for the motors was nice to verify with the CAD model.

The tough part will be welding aluminum brackets to the cast aluminum trucks in order to mount the carbon…

[Grolletje]

Really nice thread!!

[Morgan]

I’m thinking this might be better as a 10s rather than a 12s system considering the higher kv of my motors (kv295)

[Morgan]

Sending files to get cut out of carbon plate today. This is my first time mounting motors like this. Does this look like it would work?