First of all, let's see what we need for this project. I wanted double motors, double ESCs and so on, but since I received the board after I've ordered the components, I couldn't know the size of each wheel, shaft, etc... The motors I have are too big for my board to be one next to each other... Any way, the main aprts are a 6S battery, an ESC, a burushless motor, the radio control and the receiver, the motor mount and the longboard.

1 x Arduino NANO: LINK eBay
1 x N5065 400KV 1820W motor: LINK Banggood
1 x 120A Racerstar ESC: LINK Banggood
1 x 2Ch Radio control with receiver: LINK Banggood
1 x motor mount kit: LINK Banggood
1 x ON/OFF switch: LINK eBay
1 x push button: LINK eBay
1 x 6S Battery level indicator: LINK eBay
1 x 6S battery pack: LINK eBay or see HOMEMADE
1 x Longboard: Example LINK eBay or just buy locally
1 x big wheels pack: LINK eBay
2 x T plug connector: LINK eBay
1 x Lipo Connector: LINK eBay 
1 x thick wire: LINK eBay

Some extra parts are the battery level indicator so we could see when to recahrge the abttery, an on and off switch to power the ESC from the outside of the case and another switch to power on the entire baord. Also some battery connectors, wires and a case for all the components. Later we will 3D print a good case fro this project...

Once we have all the parts, let's look over the schematic. As you can see below, we haev the battery connected to the entire system but with a main switch. The battery also has a second plug so we coulld charge the battery. After the switch the ESC and the battery level are connected. From the ESC we get 5V to power the Arduino and the radio receiver. To the Arduino, we will later uplaod a small code that will map the PWM values as we want.

To power up the ESC I will later solder a push button to the ESC. The brushless motor is connected to the ESC and that's pretty much it. The circuit is very simple. We will also need the radio transmitter. 

If we connect the radio receiver directly to the ESC we would have problems. The rotation would be very abrupt. Also the break and we don't want that while we are on the longbaord otherwise it would trow us from the longboard. To avoid that we first read the PWM signal from the radio receiver with an Arduino and then we create our own PWM signal in the range taht we want and with the dealy we want.

In the vide below we can see the difference between using directly the PWM signal from the radio receiver or use the maped signal with the Arduino and also a small delay. In this way, it is much safe to ride the longboard. Downlaod the code and uploade it the Arduino and make the connections as in the schematic above.

Below you haev the STL files for this project. You will need a printring area of more thann 28cm to print the big case. That's why I've used my Creality CR10 for this job with a printing area of 300 by 300 mm. You don't need support and the aprts are already oriented and ready to print. Donwload the files, create the G code and print.

I've used a 0.4mm nozzle and 0.3mm layer height. I've used PLA material and with 15% infill and 2 perimeters and it took me aroudn 25 hours to print all the parts. You have 2 cases and 2 top paltes for each.

Mark the holes and drill them using 3mm drill bit. use cone shape head screws so they will end flat on the board. Screw the case in place and make all the connections as in the schematic. Close the case using other 3mm screw and nuts inside of the 3D printed case. That's it.