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How One Silicon Valley Engineer Hacked Together A 3D Printed Electric Snowboard This Weekend

Whilst most of us Bay Area Folks were lazing on the couch this weekend, Jude Gomila, Co-Founder at Heyzap hacked together a 3D printed electric snowboard.

Now for any of us who have been snowboarding know it’s a pain in the ass when there’s an upward slope having to unstrap one food and hobble up the slope, looking rather silly, whilst skiers use their ski sticks to glide them slopes, beating us boarders to the apres ski bar.

The TechDrive team think this could be the next BIG THING and think Jude should patent this and get it to market straight away, here’s how he did it in his own words:

You have probably seen snowboarders getting stuck in the flat parts of green runs and connecting paths while skiers skate past them.

A snowboarder has two realistic options at this point: either completely bomb it down the approaching slope at dangerously high speeds or build a 3D printed electric jet-powered snowboard. I chose to do the latter.

Inspiration

After watching Adam at Dreamscience pull off a handheld electric jet snowboard I decided it would be fun to build a board mounted jet. I was not too keen to wear a backpack or to hold a bulky bar but rather reach the freedom of the mountains by putting the electric jet directly onto my board. I’m going to walk you through how to make it, skipping all the failures and iterations that I undertook to make it work. Word of warning: this jet is a fairly dangerous project that could electrically fry you or cut your fingers off from the RPMs of the jet. Do not make it if you don’t have electrical experience at currents that will kill you and mechanical experience such that you won’t cut your face off.

Step 1: Making the 3D model

I used Tinkercad to create the model. Mostly by eye and using my memory of the board dimensions for measurement. If you want to modify my design please find it here. The design is pretty simple and allows for a battery to be placed at the front with enough support to hold around 22lbs of thrust from the jet. There is a small hole carved out for the electronic speed controller.

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Step 2: Printing the mount

I 3d-printed the mount using an Ultimaker 2 printer. This was done in 4 parts as the entire unit will not fit into the build area of the printer. Here are the 4 parts below which are to be glued together using Super glue.

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Step 3: Mounting the jet (EDF)

The jet that I picked is something called an electric ducted fan. It has a max thrust of around 22lbs (enough to push me on a snowboard). It draws 120 Amps (which is a fairly dangerous current @ 50V) with a max capability to draw 6000 watts (which is around 6 kettles running). So essentially to power this beast up, you need some serious battery power and a decent electronic speed control. Below is the picture of the mount fully super glued together and the jet glued using Gorilla glue to the mount.

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Step 4: Designing the electrical setup

So the jet is linked to an electronic speed controller (ESC) (similar model to what I used here). This speed controller allows for controlling the speed given a certain input from a servo controller. It is pretty industrial and can run up to 150Amps @ 50V. The ESC is connected to the battery. The LiPo battery can have 120 Amps drawn from it at 44.4V (12S) and is rated at 4000mAh, meaning I would have around 4 mins of battery time at max thrust (or 8 mins at half power). An important part to note here is that everything must be electrically matched up in this elegant rig (voltage, max current draw etc). I made some modifications to the wires and soldered on connections to connect the jet, ESC and battery. The ESC itself needs something to control it. I bought a cheap wireless throttle that essentially outputs a servo signal. The receiver of the wireless throttle was powered by 4 AA batteries. Additional note, I used 2 low-voltage warning circuits that connect into the battery that tell me if my battery was running low on power (this was mostly for safety so as to not damage the battery if the power was running low – these hi-power batteries can be damaged if you draw power when they are on low charge). I threw in a typical charger that you would need for this type of battery.

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Step 4: Testing the electrical setup

Once everything was soldered and plugged together I systematically tested all the subsystems to make sure they were safe and well connected. I fitted the jet to a rig for basic testing using a servo controller rather than the wireless throttle. I used liquid plastic to electrically insulate the wires and reduce risk of shock. Here is a video of one of the tests on the rig!

Step 5: Full mounting to board

Once the test rig worked I glued the 3D printed mount to the back of my snowboard. I glued in the jet and fitted the rest of the electrical components as shown here:

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Step 6: Full test of rig on board

Now that the glue had dried, everything was ready for a full rig test of the board.

Step 7: Outdoor test

After testing indoors I was ready for the full scale outdoor test. I tested it in Kirkwood, Tahoe, US and it worked! Holding the gopro camera and throttle was a little tricky but the ride was smooth. I got speeds of up to 15 mph on the flat.

Future modifications

  • Adding a flexible layer between the mount and the board to allow easier turning and keep the mount connected to the board.
  • Allowing a sliding connector so the mount can be removed and put back on at any time.
  • More waterproofing.
  • Adding some finger guards and safety.
  • Better calibration of the wireless controller.
  • A safety cut off switch.
  • Switching to gas jet turbine 55lbs of force for uphills and more safety.