Instructables

Electric TurfBoard (FAIL)

Picture of Electric TurfBoard (FAIL)
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The concept of electric skateboards has always piqued my interest; they are the closest thing we have to Marty's McFly's hoverboard. There is no lack of working production models and cool DIY projects:

http://www.instructables.com/id/DIY-Electric-Skateboard/
http://www.instructables.com/id/Propeller-Powered-Skateboard-1/
http://www.instructables.com/id/Easy-build-self-balancing-skateboardrobotsegway-/

I wanted to take a crack at it myself, but the components seemed more expensive than the a fully functional board (≈500$). Once I saw the "Turfboard Deville" being liquidated on Ebay, I knew I had to make it happen. Skip to the last step to see the disappointing results (so far...maybe) otherwise check out what I've attempted to do in the steps. Feel free to comment if you have an elegant solutions to my design issues.




 
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Step 1: Hardware

The Turf Deville is a trully HUGE BOARD: tall and long enough to tuck all the components neatly under the board. It is also gnarly looking with knobby tires, and red spring. The people that developed this beast must have lost their shirts developing and manufacturing it. The reviews online unanimously panned the board for being too heavy, unmaneuverable and implementing an obsolete snowboard binding system. None of these were cause for concern for my project.


 
Note that the kids in this video likely have had their knees replaced... (did I mention heavy?)

Items that I used for construction (failed attempt):
  1. 48v-1000w-motor-controller-throttle-kit at Monster Scooter Parts (180$)
  2. TurfBoard Deville (80$) no longer available...
  3. 48V Lithium EBike Battery at Golden Motor (470$): I already have this and have been using it for other projects such as the Electric-Snowcat-Pico
  4. Sprocket set that fits onto the motor and brake cylinder (30$)
  5. Handle bars from a Razor E200 scooter
The sprockets was more of a challenge than expected. The tip on the motor is not "D" shaped but rather, it is flattened on two sides. I eventually went to a machine shop to get a sprocket to fit as well as boring holes and threading them into the brake cylinder into which I attached the wheel sprocket (both from pocket bikes).
GlowGuy1 year ago
Try looking at sprocket guards. Round piece of metal that attaches to the sprocket, looks like a sprocket with no teeth. One on either side with enough of a gap to allow for the chain.
Renard_Bleu (author)  GlowGuy1 year ago
Thanks for the comment.
I hadn't considered that, I could make one out of sheet metal and attach it to the sprocket with some washers to give it some space. Thanks for the comment.
You could try a "V" belt. Perhaps an undersized one so that if it comes a little loose it will still stay in the pulley. They are very inexpensive and will still function if they are slightly out of alignment. I believe the chain is coming off not because it is loose but because the suspension is compressed on one side when you turn or shift your weight. This would then put the sprockets out of alignment with each other and the chain would come off.
Renard_Bleu (author)  messyworkbench1 year ago
Thanks for the comment. I'm a little bit of a bike nut so I would not have considered a belt. But a belt might just be the solution I'm looking for!
I used to work for Goodyear a long time ago and V belts were one of the products I sold. Good luck and if you could send me an update. You could look at pulleys from a furnace blower or various car engine parts. Any store that has parts for the agricultural market would have a good supply as well.
Paul
Renard_Bleu (author)  messyworkbench1 year ago
I actually cut a few out from my snowcat project... I'll try to save them next time.
I think your issue is that the motor is mounted to the board and the wheels move independently from the board due to the suspension. This is going to cause the chain loop distance and angel to vary not just in turns but also as you apply power. I have one of the professional models that works pretty well, but I rarely use it. It also suffers from a poor turning radius and must be used in big open areas (not what I bought it for). The motor on the board I have is mounted to a plate that mounts directly to the axel. This keeps the chain length and angle fixed. You could try to mount the motor to the suspension arm of the wheel you are driving. That should keep the chain distance and angle constant. It would also allow you to loosen up the suspension for a better turning radius.

Before I bought my turf board I thought about buying buying a used electric scooter and mounting the rear drive to the back of the turf board (making it a three wheeler). You might try that as the motor drive will already be worked out. A used electric scooter should be pretty cheep if the battery is dead. You could always buy a longer set of trucks for the front if you want more stability. If you keep the scooter handle bars, you might try shortening the distance between the front and rear wheels for a better turning radius.

Thanks for sharing your experience!
Renard_Bleu (author)  dirty_valentine1 year ago
Thanks for the awesome input. I had started a new comment instead of hitting reply...

I had considered mounting the motor directly on the truck/suspension, but the motor is HUGE and didn't fit. I am sure I will pick this project up in a few months (I get heartburn just looking at it now), and I'll be sure to update this instructable.
Hmmmm yeah use a FIXED single or dual real wheel and a truck up the front.... and only drive the rear.
The other idea is to use the deliberately flexible 21 - 27 speed bicycle chain and a kind of intermediate re-railer, kind of like what the bicycles have....

But the single driven rear wheel seems much easier.
Renard_Bleu (author)  Wroger-Wroger1 year ago
Thanks for the comment. I was considering threading a single rod across both axles (both on the back) as a next step. Good idea on a tensioner as well.
Don't give up, you are so close to having something really fun.
It looks like you chain problem has to do with the location of the suspension pivot point and the location of the drive motor. In a perfect world you would like to have the motor shaft and the suspension pivot in the exact same location which would eliminate the chain from going tight or slack depending on the amount of suspension compression. This would be a lot of work requiring an intermediate shaft and a second chain. So an other option is to relocate the pivot point onto an imaginary line drawn between the axis of the motor and the axis rear wheel when the rear suspension is compressed to its normal operating mode ( look at a motor cycle and you will see that the three points are always close to being inline). A third option is eliminate the rear suspension. Do you really need it? Those tires look like they will soften the ride. Does the board have independent suspension, if so, that might be part of the turning radius problem? Try replacing the rear shocks with a metal bar or blocks of wood to see if that helps with the chain problem.
Good Luck
Renard_Bleu (author)  mygirlsrock1 year ago
Thanks for the comments

In fact the suspension is more of a decoration, there is very little movement on that axis. I have also considered using a single threaded rod that would bridge the "independant suspension" that would serve to keep the mounts from flexing apart.
I have a some great solutions to test now, thanks to all the great suggestions everyone. I will update...
Renard_Bleu (author) 1 year ago
Great suggestion. I would not have considered that.
Renard_Bleu (author) 1 year ago
Thanks for the awesome input. I had considered mounting the motor directly on the truck/suspension, but the motor is HUGE and didn't fit. I am sure I will pick this project up in a few months (I get heartburn just looking at it now), and I'll be sure to update this instructable.