Most of the electric skateboards for sale today are big, heavy, and ugly. The company promising to change that, Boosted Boards, is charging nearly two grand for a pre-order. I decided to make my own, using the same basic setup that Boosted uses: a real longboard deck and a compact brushless motor.
On a forum called EndlessSphere I found a group of people doing exactly what I wanted to. Most of the other homemade e-boards use kit motor mounts, but their advice on batteries, gear ratios, and motor selection was critical. For the most part I went with the cheapest components possible, which proved pretty hit-or-miss.
Here’s my setup:
Rayne future killer deck: I figured if I was going fast, I want to be on a solid stiff board, so went with this awesome downhill deck with W concave that I bought used.
Turnigy Aerodrive SK3 55mm 280 kv brushless motor: A lot of people run two motor setups, sometimes even 2 60mm's, which is awesome but requires more batteries, speed controllers, and results in a heavier board. For me (155lbs), one 50mm SK3 proved plenty. Acceleration is good and it tops out at 20.2 mph on flat ground.
Belts/pulleys: I went with a 14-tooth motor pulley and 29-tooth wheel pulley. The belt is as short as possible for an extremely compact drive terrain. Most longboards on EndlessSphere use large wheels, but I didn’t want to change the ride characteristics so had to go with smaller pulleys. The small drive pulley does occasionally slip, but I’m fairly light and have been able to get away with it. I opted for a plastic motor pulley with an aluminum hub. My first one lasted just a few minutes before the plastic stripped from the metal. I drilled a hole through my new pulley and a pin keeps the two pieces from rotating. If I did it again I would go with an all-metal motor pulley. The plastic wheel pulley works fine, I just got it perfectly aligned and glued it down to hold its place, then drilled in holes and used 5 screws with really wide threads to attach it. No bolts, just directly into the rubber. Because my wheels had perfectly flat inside walls, this worked fine, and has not loosened.
Hobbywing EZRUN 150A-PRO ECS: This is my second speed controller. I ran into an issue with my first speed controller, which was intended for rc boats. I abandoned that for the Hobbywing ECS. I am extremely happy with this choice. It has an integrated on/off switch, is easy to program, has LED's to indicate low voltage/ overheat, and just feels easier to control then the boat ECS.
2 2350mah 30C Lipo batteries: I went with two thinner 3-cell batteries instead of one 6-cell brick. They only give me around 30 minutes of riding, sometimes less with hills, but that's enough for getting around campus. If I decide I want more range I'll probably go with swappable batteries, instead of one larger one.
Homemade motor mount: This is the most difficult part of making an electric longboard, but as long as you can find someone who can weld it's not bad. It took me a while to find someone who could weld, and once I did I had him attach a block of aluminum to the truck. This would serve as the mounting point for the motor bracket, but didn't get in the way as I was riding the board around before getting the motor. Having a block like this also means I can replace broken motor mounts and remake my motor mount if I decide I want a longer belt or want to motor to be higher off the ground, etc. It gives me flexibility. The mount itself is just a 8mm aluminum slab with some holes drill in it. The holes aren't slotted, because I heard some stories about people's motor shifting slightly over time and forcing them to re-tighten the belt. Mine has one poison, and the belt is tight. I was worried that the belt would loosen up over time as it wore in, but that hasn't happened, maybe because the belt is so short.
PVC Plastic electronics cover: My electronics are attached to the bottom of my board with tons of those removable dual-sided adhesive tabs used for mounting hooks to walls. The wires are a hideous mess, but at least they are covered by a pretty nice enclosure. Using a heat gun, I worked the pieces into shapes that would fit together and cover everything with the smallest amount of wasted interior space. The enclosure is attached with heavy duty velco-like strips. It is all sturdily mounted, and there is no damage to the deck. I'll be painting it black soon, because the white really shows any dirt and mud that splashes up on it.
https://www.youtube.com/watch?v=aVv0oPY6ZDo
