My friend still has two years of uni left in Edinburgh. Due to rent being stupid high, we’ve never lived particularly close to school. I could afford an esk8, but he could not. But I didn’t use my esk8 every day anyway, since it rains very often in Edinburgh, and the strong winds and hills require a powerful board.
this sucker my friend agreed to edit a 20-30min long youtube video for me if in exchange I built him a 2000€ electric skateboard for commuting in Scotland. Time = money so the deal makes sense for me. So, how are we going to do this?
- Enough range to get to school / fast charging
- Easy to carry around campus
A high-performance skateboard for this cheap ain’t easy. So here are the parts I ended up with:
- Surf Rodz RKP baseplates used from @BigBen for dirt cheap
- 3DS FatBoy Surf Rodz 260mm hangers to match
- 3DS 4:1 SS HD-Mini helical gear drives (Because belts slip and we need that efficiency & torque!)
- 3DS hubs in gunmetal grey (Not that much more than plastic hubs tbh)
- LY Evo 40" deck (bought in the US because of availability and price, shoutout @JJHoyt for being the middleman so I could take this back to Latvia)
- Double stack Evo enclosure from @BigBen (Cheap, and the wide enclosure lips make this ideal for waterproofing)
- Stormcore 60D+ used from @poastoast for dirt cheap (Reliable ESC with dual UART for a robogotchi and Kami remote) (Shoutout @MrDrunkenMobster for being the middleman)
- 20A charge port from DuckBatterySystems
- Mini remote from Nexusboards (dirt cheap, and it’s a trigger remote!)
- Metal risers from Trampa (Cheaper than Riptide tunnel risers, although they’re conductive so in hindsight this was a mistake)
- 6.5" Urban Treads from Trampa (larger wheels would cause wheel-bite)
- Radium anti-sink plates (I was buying stuff from him anyway, and 3DS was OOS on theirs)
- Maytech 6374 190kv motors bought new from @FreezingShrine
- Riptide Krank bushings
- Black MR60 connectors from @PixelatedPolyeurthan
- 10s4p P42A battery to be built by @Anubis
Marking where to drill the holes on the enclosure was one of the hardest parts. The enclosure isn’t symmetrical at all, so a lot of painters tape at 90 degree angles was needed to get somewhat even hole spacing.
Also, this time I only drilled 4 corner holes in the deck, added inserts, bolted the enclosure, and then marked where to drill the remaining holes. They were pretty spot on this way!
Also counter-sunking the holes for the inserts and using a spare bolt and two nuts to lock the insert to the bolt was required to get these in. Definitely the hardest part of this build.
And I even managed to fuck up once because my tape marker on the drill bit had slipped up and I drilled too far, ruining the beautiful grip-tape
Also some of the inserts got their inner thread fucked up and then got stuck to my bolts, and got pulled out, despite the epoxy and everything!
All was well eventually. I did make the enclosure holes larger (M6) in the end. The washers cover it, it’s fine.
I’m running a 35 degree baseplate up front, and a 45 degree baseplate in the back. With the Evo’s angled ends of ±10 degrees, this ends up a 45:35 split again
One large mistake I made was using an LP-20 charge port.
- The rubber flap comes off easily, so it gets full of dirt
- It’s huge! I only had 1 spot I could reasonably put it, and because of it the ESC sits slightly too far back and I can no longer fit a 12s4p P42A pack
- Good luck finding a 20A charger anyway
I’m now switching all my boards to SP-13 connectors because they’re more sturdy, smaller, can do 13A and most importantly – have a screwable cap on them! You can get them on aliexpress or from Apex Customs.
Anyway, how do we make the motor connections waterproof? Phase wires are easy – epoxy some MR60 connectors and bob’s your uncle. I even added 4mm bullets both on the inside AND outside so that the ESC or motors can be easily replaced.
But the sensor cables? Well, as you’ll see in another build thread of mine, waterproof sensor cables take up a TON of space. Like look at this spaghetti mess!
My solution for this board: A single cable gromet, that I can just barely squeeze both sensor cables through if I depin them from the JST connector!
Oh, and I also conformal coated the hall sensor PCB on the motors. Standard practice for me these days.
To be extra safe, I covered the charge port and power button openings with some sort of white silicone cream on the inside. I also used fabric tape to secure the small wires from sensors and the power button together. All the cool kids are doing it. (Shoutout @mariocontino )
The cable gromet is epoxied in of course, but for safety I also squeezed some butyl tape in there.
I assembled the gear drives with green threadlocker (I’ve found that red isn’t strong enough). Because the bushing seat opening is too small on these trucks (see my green board thread), I’m using cone bushings with the narrow ends towards the hanger. Not buying these trucks again, wish I knew before I had ordered them.
I put some fish-paper on the metal risers from Trampa so that the wires wouldn’t cause a short if they got cut up.
The motor wires go between this riser and the deck, and and connect to the MR-60 extensions I soldered. Once the enclosure is mounted I duct tape these wires to the deck, just so that they’re not hanging loose. The motors leave perfect space for the sensor wires to go up into the gromet. Perfect fitment
I really like that the motors are forward mounted, yet high up. You can drag the board by lifting the front, and not have to worry about the motors hitting anything. Very practical.
Also, I got some M3 washers so that the plastic gear drive bumpers wouldn’t fall off like they did on my green board. Lesson learned.
I put a 10s4p 30Q battery in to test ride this board. Unfortunately I finished it a day before Latvia would be covered in snow for a few months, so I had to test ride in very rainy/muddy conditions. When it’s fully assembled a layer of butyl tape on the inside of the enclosure bolt holes will keep the enclosure water-sealed, but for this test I just used foam and duct tape. And it survived!
I took the board apart and washed it off. Bought shorter enclosure bolts, and added some water ingress detection stickers on the inside, for future reference. @Anubis will be building a 10s4p P42A battery for my friend, which should give him 20km of range. Wish we could fit a larger battery, but this double stack enclosure is really small, and not thick enough for a 21700 double stack really. But oh well, with 10s the top speed is about 45km/h which is fine for my friend, and the torque at 70A per motor is fucking fantastic
Hopefully my friend takes some pretty pictures of the board and his adventures when he gets to ride in in the UK in two weeks. The total price of the board, including the 10s4p battery, ended up being 2100€. Not bad for a gear drive DIY build IMO. Thanks for reading!