45+ mph top speed
35 mph cruising speed
7.5 HP ( 6400 watts)
18 mile range
Forget what you thought about electric long boards. This isn't some 15 mph toy cruiser. This is a dual wheel drive monster, and its two motors combine to make 7.5 HP of raw brushless power. This is the supercar of small electric vehicles that brings a thrilling experience by replicating the feel of long-boarding and snowboarding with sport-car like propulsion. Who said you can't carve up hills? This extremely unique combination provides an incredible new way to travel that any thrill seeker would enjoy.
Step 1: Get All Parts Needed
Wheels and trucks
Deck - longer is better
Receiver and transmitter
Batteries - 10s high capacity/discharge
Power Analyzer - watt meter, power consumption
Motors, ESC, Power Switch
BATTERY CHARGING HARDWARE :
Battery Charger - get what you pay for
Power supply - buy higher wattage than battery charger is capable of
Parallel charge board
ODDS AND ENDS:
10 gauge AWG stranded wire
Heat Shrink 10 gauge
6x 1/4" by 2.5" bolt
6x 1/4" - 20 nut
4x M4 by 12mm bolt
4x M4 washer 2.5" washer
6mm strip of aluminum
WHERE TO BUY:
The prices of these materials fluctuate quite fast, but doing your research and looking for the best option to fit your goal is the way to handle your project. I chose the best materials to build the fastest board I could make.
Step 2: Wiring / Putting Together Battery Charger
Building this charging system is not easy; there are many things to consider in building an efficient battery charger. First, I started with sizing the power supply appropriately. The power supply powers the battery charger. This charger (like any other charger) can normally only charge one battery at a time, and I have four batteries (each of the two packs is composed of two 5S batteries in series). The Parallel charging board I constructed makes it possible to charge all four batteries at once. I sized all my materials appropriately and after soldering everything nicely together I used heat shrink to make the professional finish.
A little about LiPos
First you must understand that is is one of the most complicated LiPo battery types, and thus is one of the most complicated battery charging procedures. I designed this system to be able to charge both (which is in essence 4 batteries) for my longboard at the same time, making the charging process faster. Before moving onto this step, it is recommended to get on you-Tube and research what LiPo batteries are and how to charge them (trust me, it will save a whole lot of heartache).
Basically you want to understand :
S = nominal LiPo voltage 3.7 (So a 10S battery = 37 volts)
There are 3 stages to LiPo discharging. Full charge = 4.2v ( quickly discharges to nominal and stays steady), nominal LiPo voltage = 3.7v ( steady at this voltage until closer to end of capacity), Cut off Voltage 3.3v (it is not good to run these batteries completely dead, so 3.3 volts is the accepted safe cut-off point).
C = Capacity, and deals with Discharge rate. To break it down to its simplest terms, the C rating is the maximum safe continuous discharge rate of a pack. If you see 10C on your battery, it means it can be discharged at 10 times that pack's capacity. Capacity refers to the milliamp-hour rating of the battery, which will be listed as a number followed by mAh (2000mAh, for example.)
I have two of these bad boys and have them tied together in parallel to provide a 9 Ah system. This is far beyond the commercial electric skateboards in terms of storage/performance (10S vs usual 6S = faster motor RPM/more power). This translates to longer range, more torque for the motors, faster riding, and less strain on fast accelerations on the batteries.
Step 3: Designing / Cutting Motor Mount
By first getting the hubs and belts tightened by hand, I measured and designed a design on paper that could easily be machined out of a 6mm (quarter inch) strip of flat aluminum metal. I suggest doing this after you acquire the correct belts to make sure that you didn't design a mount that can not be tight with your materials. These lengths fluctuate with different sized cogs / gears. The design that i chose allows the motor to be mounted on a variety of different sized belts and cogs, and allows the to be tightened by simply sliding and re-tightening.
I custom designed my own motor mounts and programmed a CNC machine to cut them out.
WELDING ONTO TRUCKS
I then TIG welded the trucks and reinforced with custom brackets and chamfers. Welding these motor brackets to the truck was a little bit tricky, but inexperienced welder should have no issue with this.
Step 4: Fit Gear to Motor Shaft
Next I keyed the motor gear.