Hey all, I'm usually shocking at documenting projects, but this time I'm determined to take pictures as I go and write stuff down. I hope someone finds this project interesting.
I built an eBike to commute to Uni a couple of years back, and after doing 3000km on it decided to sell it on. 6 months later I have the bug again, and have decided to build an electric longboard.
I've had this Original Apex37 Carbon for about 5 years now and it's served me well. I really like how it rides so I think it will be an ideal platform to strap a motor to.
18650 cells seem to be an ideal form factor, with a good compromise between robustness and energy density/power/cost etc. I went for 50x Samsung INR18650-25R, in a 10S5P configuration. Here's the cells hotglued together for prototyping and making sure they'll fit.
I had some silicone insulated 6AWG multistrand in my shed so figured I'd use that and save some money. Turns out it was far too big.
The wire was made of 7 main strands of copper twisted together, with each strand consisting of a whole bunch of little strands...if that makes sense. I stripped the insulation off the wire and re-wound it into two groups of three, with a single strand left over. This was a more suitable thickness, which I bent into shape and tinned with solder.
The 18650 cells have a thin anti corrosion coating on the terminals that solder doesn't wet to, so that was scraped off and the terminals tinned. I've soldered 18650 cells before, and found it doesn't damage the cells if you're quick and use an iron with a high thermal mass. The iron doesn't make contact for more than 2 seconds.
Here are the cell groups soldered up, and how they'll be laid out under the board.
They will ultimately be housed in a DIY wet-laid carbon fiber enclosure consisting of 4 compartments to allow for board flex.
Onto the motor:
After doing some research it seemed as though the Turnigy SK3 6374 192KV motor would be a good candidate to power the board.
This thing is huge. I love it
That's all the progress I've made so far, but I've got heaps of stuff in the mail so hopefully this will be a quick build. The most laborious aspects will be designing/making molds for the carbon fiber, and designing the wireless remote/modifying the (incoming) VESC software to suit.
This is a brief overview of the direction I'm hoping to take the build. Stay tuned..