This guide should explain how the mechanical parts of an electric skateboard go together.
Contents: (Click to jump)
1. Basic Mechanical Parts
Basic mechanical parts are those that are normally found on a regular skateboard or longboard.
The parts include:
Stability at high speed is important if you are putting an electric motor on your board!
Four things you want to consider for e-boards are wheel size, wheel shape, truck size, and truck shape.
Wheel size is important for two things: speed/acceleration and traversing bumps.
Bigger wheels can give you higher top speed, but cause slower acceleration and they also make bumps less prominent. Longboard wheels can vary from 80mm to over 90mm in size, feel free to go bigger if you can find them.
In order for the motor to drive one of the wheels, a pully needs to be attached. The wheels you get need to have bolts go through and attach to a pully. This might mean dedicated holes in which bolts fit perfectly, or drilling your own holes for the bolts. ‘Flywheel’ is the name given to a wheel that can be powered.
Truck size has to do with stability, wider trucks are more stable than narrow trucks. Truck size varies from ~120mm to over 200mm.
You might want to consider truck shape as this is where your truck clamp/motor mount will attach.
A lot of truck clamp designs have a flat side to stop it spinning, and so your trucks would have to fit this design (“caliber” style). Make sure you know what truck clamp you will use before buying the trucks. Alternatively, you can weld the motor mount to the trucks in which case the truck design is less important.
2. E-board Mechanical Parts
These are parts you would not normally find on a regular skateboard or longboard but do not include any of the electronic parts like the motor or ESC.
Note: if you use hub motors you will not need anything in this section.
The parts include:
- Truck Clamp
- Motor Mount
- Timing Belt
The truck clamp connects to both the trucks and the motor mount. As it directly connects to both of these, it needs to be compatible – most motor mounts will easily fit together with the truck clamp, it’s the trucks you need to be careful with. Most truck clamps are built to fit the ‘caliber’ style of truck which has a flat bottom to stop the clamp from slipping.
The motor mount connects to the truck clamp and to the motor itself. Most motor mounts are adjustable to allow different sized motors to fit and to keep them from scraping on the ground.
Note: in some cases, motor mounts are combined with a truck clamp in one piece so there is no need to buy both.
Drive Train System (pulleys & timing belt)
Like stated before the pulleys need to fit whatever they’re attaching to. So, the large pulley needs to fit the wheel, and the small pulley needs to fit the motor.
It can be confusing when trying to choose the sized of pulleys and belts because it affects the gearing ratio of your board. There are the pitches (size of the teeth) of your belt and pulleys which need to be the same, size (number of teeth) of both the large and small pulley, number of teeth in the belt and the length of the belt. There are tools like this one, that can help you to calculate these sizes.
Alternatively, you can buy kits which include pulleys and belts together which make matching them easier.
The diagram above shows a top-down view of how the mechanical parts (plus the motor) go together.
The diagram below is a real-life example of how the parts fit together.
4. Minimalising Vibration
Heavy, excessive vibrations can cause electrical connections to fault. Reducing this can make your e-board last longer before it needs repair.
You are not going to stop vibrations but there are a few things you can do to help reduce them:
- Use rubber truck risers
- Use rubber pad(s) when attaching the housing
- Use big(er) wheels
- Secure the electronics inside the housing e.g. don’t have loose batteries/VESC
Another must when it comes to vibration is to use thread-locker on screws and bolts, the vibrations can cause them to come loose.