Author Archives: kimsong

How to Build an Electric Longboard

My name is Kirs. Maybe you’ve seen me on campus. I’m the guy who rides around on an electric longboard. I’m usually wearing sunglasses and earbuds and sometimes even a helmet, but what makes me stick out of the crowd is when I zip past you at 25mph with a 3.5 horse power motor buzzing under my feet. The culprit of these sounds is an electric longboard that I had built over the past summer. Building an electric longboard was one of the best decisions of my life. However, electric longboards are new pieces of technology so I’m writing this to clear up some of the misconceptions and maybe teach you how you can build your very own electric longboard.

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Why get an Electric Longboard?

So an electric longboard or “e board” is just another type of electric vehicle, there is no gas engine; the energy comes from a battery.The amount of energy required to charge my board is just pennies for a full charge and can last me for miles. Not to mention that I am reducing my carbon footprint by not being reliant on gas. You might be asking, why not just use a normal longboard or skateboard? The answer is simple, an e board can take you further and faster then a traditional board could ever take you. Riding an e board is it’s own type of fun, and is honestly more enjoyable then tirelessly kicking around campus on a traditional skateboard. It feels like you are always going downhill.

So an e board can transport you for miles, at speeds as up to 30mph, and doesn’t use gas; that sounds a lot like a bicycle. I’d have to say that e boards and bikes are very similar. They fill similar transportation niches and cost very comparably with prices ranging from $300 all the way to $2000 and up. I personally prefer the e board, obviously, but that’s just my opinion. They both have their pros and cons and I highly recommend people to consider the options and make a decision dependent on your needs.

Bikes are safer, better at rougher road conditions and never runs out of battery life. E boards don’t require any of that peddling nonsense, allow you to go as fast or as slow as necessary, and don’t need to be locked up every time you go inside a building. The biggest drawback with an e board is that you have to carry it everywhere you go, but that also means that you can easily switch from pedestrian to “cyclist” which lets me zip around campus very quickly. There have been many times I have stepped out of my dorm on Orchard Hill, zipped to my class in Herter Hall, and ran in, all in under 3 minutes. I don’t have to walk to the bike racks behind my building and unlock and lock my bike every time I go inside. My vehicle is at my side at the ready. Many times I’ll zip from classes, dining halls, and dorms but will find myself in situations where I need to walk. Let’s say I’m getting lunch with my girlfriend and we are headed to Hamp dining hall, I’d just pick up my e board and walk along next to her. Bikes are great at getting from one place to another, but electric longboards make every journey an adventure.

How to build your very own E-Board

So I have you convinced that you need an electric longboard (Or you just skipped to this section), and you want to know how to build one. Let me get one thing straight before you begin planning. There are two things that you need to keep in mind, effort and money. The more work you decide to put into the board the more you can customize it and also reduce costs. You could go as far as to CNC your own aluminum mounts and carve your own deck out of maple tree you cut down yourself, or you could go the zero effort route and just buy a Boosted Board V2 for $1600 and call it a day. I did something in the middle. For my build I didn’t require anything more then a power drill, some allen keys, and a soldering iron. It can vary a lot depending on what resources you have. So keep these things in mind when planning your build.

I had no experience in motors, electrical wiring, batteries, or anything ‘DIY’ before this build. I was just some freshman with a highschool level of physics under the belt and a problem that needed fixing.You don’t need to be an electrical engineer to build an electric longboard, you just need some passion, time, and money. So I’m just going to spit out the specs of my board, but I’ll explain it after so don’t get worried if you don’t understand.

  • Board – Beercan Boards 40″ Kegger DTP
  • Motor – DIY 6355 (230kv, 2650W, 12S, 80A)
  • Battery Pack Cells – 10s1p 8,000mAh LiPo
  • ESC – VESC
  • Wheels – 83mm Wheels (Black)
  • Drive Pulley – 13T Motor Pulley
  • Wheel Pulley – 36T Drive Wheel Pulley
  • Belt – 255mm High Torque Timing Belt
  • Controller – WiiMote

So my board costs about $900 which is middle of the road in terms of price. If you just want a campus cruiser to get you to class then you could easily get a build done for $400. Be aware that going on the cheap in terms of certain parts can really hurt your performance, range, and reliability of your E board. Let me give a breakdown on all the parts and what the importance of each one is.

Board – The actual deck is very important. This is the part that you will be strapping all your electronics to. You can buy a new board or use a board you already have. You don’t need a weird aluminum deck like mine, wood will suffice. I recommend longboard decks, boards of length of about 36″ or more, over normal skateboard decks because it allows for more space for mounting things underneath. You can get pretty creative with this part and find a board that’s unique.

Motor –  Motors come in all shapes and sizes so you should checkout a hobby shop or hobby parts website. This is where things get all “engineer-y”, it’s not that bad though. What you are looking for is a brush-less out-runner motor with a kv rating from 170 to 245 and watts between 1500 to 3000. So think of your kv rating as how much toque your board will have, the lower the kv the higher the torque. Watts is how much power your motor will have, more watts is generally always better. My 230kv 2500watt motor is pretty beefy and is more then enough for a single drive build.

Battery – The battery determines how far you can go. You will want a battery that is compatible with your motor. My battery is 10s1P LiPo which means I have 10 LiPo cells in series with 1 parallel line. That means the voltage of my battery is (10 x 4.2) 42volts. My motor is rated for 12s or (12 x 4.2) 50.4volts and I am running 10s, so that’s all kosher, don’t have your battery voltage exceed your motor max voltage. The capacity of the battery is measured in mAh and that determines how much juice your battery will have. I have 8,0000 mAh and with this you can determine how much energy you have in watt hours.

The formula is (current)*(voltage)/1000 = (Energy) or (mAh)*(V)/1000 = (Wh). So for me that is…

(8000)*(42)/1000 = 336wh

So for every wh of your battery you tend to get 1km of distance on your board. As you can see, my board goes very far.

Here is a great Guide to Understanding LiPo Batteries which I highly recommend you read. LiPo is a great but can also become dangerous so it is very important that you follow all the safety protocols.

ESC –  The ESC is the electronic speed controller and is the brains of your build. It connected to your controller and the battery and determines how much juice to give the motor. The one I use, and recommend, is the VESC which stands for Vedder’s ESC. Some guy in Scandinavia designed the VESC as an ESC for e boards and has become the industry standard for e boards. Just get this one.

Here is a walk-through of what the VESC is and how to use it.

Wheels, Pulleys, and Belts – So your wheels, drive pulley, wheel pulley, and belt all have to fit in together into what is referred to as a drive train. The ratio of the wheel pulley to drive pulley is called the “gear reduction ratio”. You want that to be around 2.5, but can go as low as 1.5 or as high as 3. Generally a lower reduction ratio is better. Bigger wheels mean more clearance, faster top speed, and more stability, however they also mean less torque and acceleration.

Read through this Guide to Building Your Own Drive-Train to learn more.

Controller – This is the device that you hold in your hand to control the ESC which controls the motor. I used a Wii Nyko Nunchuck but it is more common to use an RC controller because it is more reliable and does not require a soldering iron (Up until this point you haven’t needed one). I would not recommend anyone to get the Wii Nunchuck for fear of it not being set up correctly and possibly getting you hurt.

Once you have order all your parts ordered then all you have to do is assemble everything. You will still need little bits and bobs for your build. Things like screws, wires, and glue. This is just an intro to get you started and I really recommend learning as much as you can about e boards before diving in.

electric-skateboard.builders and endless-sphere.com are great forums about the e boards and has a great community full of people who can answer any questions you have.

Here is a list of websites where you can buy parts.

Building an electric longboard is not that difficult and can be a fantastic way to learn about motors, electricity, and batteries while also creating a fantastic transportation device. I hope to see more on the roads.