While I was creating my first build and began to put my first working prototype together, I figured I would document my parts, their prices, and explain why I chose them. I’ve split up the BOM into two parts, the electric longboard components and the board components which are usable on their own for a normal longboard. I decided to go with a single motor design for my first build (it seems fairly trivial to add a second motor in the future) and so far it’s been handling pretty well on hills. The only downside is that sometimes if I lean all the way to the left, the right back wheel comes off the ground slightly and I lose the driving traction. For more info about the trade-offs, check out my previous post.
The way a typical electric longboard works is, you (the rider) use the transmitter to speed up or slow down. The transmitter interacts with a receiver that is hooked up to the ESC (Electronic Speed Controller) which interprets the signal and turns it into a motor signal. The ESC needs to be hooked up to the battery for power since the ESC is what drives the motor. The motor then turns a gear which is hooked up to a belt that will then turn another gear that is attached to your wheel. This is how your longboard will gain movement.
5065 designates the size of the motor and is a common size for electric longboards although they typically have a smaller shaft. 170kV designates the torque the motor can produce (the smaller the number the higher the torque, but the lesser it’s top speed).
$25 – Wiiceiver – (Not needed if you are using the VESC)
A way to control the input to the ESC coming from the wii nunchuck
I used this in the interim while I was waiting from my VESC to be made and shipped to me. With some configuration it turned out to work decently well. I was able to ride it on flat or a slight incline, but with less power and it would cut off if the motor started to draw too much power.
DIYElectricSkateboard sells an aluminum part for the motor pulley and I figured that since it’s the part coming off the motor shaft and is only connected by two set screws, it makes sense to get this part made of aluminum to handle the stress.
Originally based off a 9mm pulley model, I had to add bigger holes for stronger screws and a couple other changes. I will link to the design I put together for this part once I’ve tested it and made it fit reliably.
This works out well and is made of aluminum. This can be replaced with a cheaper non-adjustable mount, but I didn’t like the idea of welding on a mount to my longboard trucks and had not ability to do the welding.
Due to my choice of wheels, these had to be altered in order to fit them (I used a file to make a bit of room for the screws that hold the gear onto the wheel) If I were to do this again, I might try the Paris trucks since they are more symmetrical.
Today after finishing the prints for the parts I need for my 3D printer model, I realized I had made a huge mistake. I hadn’t checked the measurements for the holes / rods and since I had gone with the US alternatives to the metric measurements, some parts just wouldn’t work. DOH!
This led to my next realization. The open source community provides the files in easily configurable SCAD files not Autodesk files or STL (STL would have been alot more difficult to edit although it can be taken and printed immediately).
In case you didn’t know, the beauty of SCAD files is that they are essentially programs. OpenSCAD is pretty much the open source standard for creating 3D objects before exporting them into STL format. It is a functional description language that dictates the characteristics of the object that allows for reusable variables and one configuration file with the power to change your whole print library! Here’s an example that creates these two rectangular blocks:
If you have been reading my blog posts, I had started using Autodesk Fusion 360 and I thought it was one of the best programs for 3D modeling. Little did I know that the open source community didn’t hand out files consumable in Autodesk and the power behind SCAD files in the open source community is how easily the objects can be customized especially since altering a bunch of STL files would take serious time in Autodesk Fusion 360.