So I live in the silicon valley, but I went off to college in Illinois and just after one semester away from home I come back to half my town riding around on Boosted Longboards. My friend rents one out and lets me try. So I go to the local skate shop and check the price. 2000$ for the one with the best specs.
This Is part one of my project to one up those greedy bastards.
- This instructable is less of a how to and more of a what not to do. I slapped together this project as proof of concept. It is not meant to be a finalized version (although can be with some minor additions). I hope it gives a reference to your personal electric board project.
- I assume you have an understanding of electronics and have read a bit about other longboard designs.
- Additionally: I do not hold any responsibility for your miss-use and incompetency. Do not attempt this project unless you know what you're doing
I will be making a Mark II in the near future... It will be a lot better
Current specs on my board:
~ 5 mile range (I use fairly shitty Lead acid batteries after I burnt my lithium ones with a shitty knock off Chinese charger)
~Max speed is over 30mph (scared to go much faster)
~Pretty buggy (Iv had it throw me off a few times)
~Able to accelerate quickly even when dragging my friends on their long-oards.
~way too much torque (Iv never had to hit the throttle all the way)
~ 25lb (I used my old aluminum deck that I make last year)
Step 1: Materials
- 2X Turnigy Aerodrive SK3 - 5055-280kv Brushless Outrunner Motor - $98.46
- 2pk 12V 9AH Battery RAZOR Scooter - $30.88
- 2X ZIPPY Flightmax 5000mAh 3S1P 20C - $49.44
- Hobbywing Ezrun 150a-pro Brushless ESC- $98.99
- Paris 180mm 43° RKP Longboard Truck - $53.99
HK-GT2B 3CH 2.4GHz Transmitter and Receiver - $23.63
Total Price: 305.95$ + price of the wheels and random hardware, and using Lead acid batteries.
Additionally I snagged the wheels off of craigslist for $30 they are the 90mm Bigfoot wheels
The rest of the hardware I found laying around in either my machine shop at college, or my shop back home.
Fuck Lipos for testing. They are so easy to damage or destroy, and if they go off while installed on the board you project is done for. Get a good charger if you are gonna use them, or a variable current/voltage supply and charge them yourself use a transformer and something like this :http://www.ebay.com/itm/311384008351?_trksid=p2060... and you'll be able to charge any batteries pretty quick. Also having a variable power supply allows you to revive old or dead batteries
Pick a better ESC than I did mine was expensive and finicky.
Step 2: Slapping It Together
I used the Mill in my shop to cut out two hold plates for mounting the motors. I cut 4 mounting slits so that I could adjust the spacing of the motor and slide it back to tension the belt.
Speaking of belts, do not do what I did and buy yourself a fucking THICK belt and some THICK gears to hold it. better yet use a chain and chain sprockets to drive the wheels
The Large black gears were 3D-printed on my friend printer. I recommend pirating or getting some freeware CAD design program, learning to use it and sending your STL files off to some manufacturer and getting them to make the gears for you. (it'll be an extra $30-$50)
I attached all the parts using either set screws or regular machine screws. I suggest welding the aluminum holders to the trucks. You are gonna need access to a TIG welder for that.
- One esc can only run one motor, unless both motors run in phase. To solve my use of having two motors. I fixed them together mechanically, So they are both spinning at the same speed Effectively turning them into one motor.
- Do not get shitty Chinese Li-po chargers. My batteries were over charged and not extremely volatile. I put them in a metal container and keep them in stored away from any flammables.
- Do no drop the board on your toes, it fucking hurts
Step 3: Ride It
Give it a small push and don't hit the throttle too hard. The thing accelerates like a breast, but unless youve welded everything into place don't hit the throttle all the way. (I haven't even hit it all the way yet except on accident, and it instantly threw me off)
Step 4: Mark II
Mark two will have a lot more functionally and a much slicker design.
- I will design all the electronic systems myself
- Redesign of the ESC myself
- One ESC for each motor
- One motherboard containing receiver module, ESCs, Bluetooth communication, USB connector, Lights, integrated battery charger.
- My own BEC standard PWN receiver/transmitter system (probably base it SCoff of the arduino processor)