This is one of those stories where the goal was to build a simple board, but things kept breaking and I had to keep rebuilding it until in the end I got something inferior to a prebuilt for 2x the price. So follow along and learn from my mistakes!
This board is meant for my youngest brother. The only requirements were:
- enough range to commute to school
- dual drive
- rideable in the rain
He liked the Bustin Sportster deck, and learned how to longboard the summer prior on it, so that + eboosted’s enclosure was the base for this build.
Version 1 - go cheap af
I repurposed the 90mm Olin Popoca wheels from my other brother’s board, as well as BN motor mounts from two previous boards. I also built a 10s3p NESE with 30Qs that was sitting around, bought from @malJohann a few years back. I went with e-caliber trucks, thinking he’d be light enough to not need anything better, but unfortunately they were already slightly bent, which caused the pulleys to scratch. A speed-ring solved that issue, but I definitely wanted to replace the hanger. Also I’m using anti-sink plates I got for free from @3DServisas. Thank you!
Pictures will help with explaining, so let’s get some going:
I’m using MT-30 connectors for the phase wires, and these 6-pin connectors for the sensors:
https://www.aliexpress.com/item/4000383092999.html?spm=a2g0o.order_list.0.0.af621802HtK39s
The screw part comes loose since it’s plastic against plastic, but a small bit of duct-tape fixes that. These connectors are epoxied into the side of the enclosure. A large downside is how long the connectors extend – this ended up biting me in the ass later.
I also made the LED connector hole too big. Was supposed to be for an XT-30, but now an XT-60 fits. Lol.
Now let’s look at the internals of the board:
There’s a lot going on here! As you can see, I had to crimp a bunch of small series connections for the NESE pack since the enclosure is segmented. (I put fishpaper on the enclosure to avoid any abrasion.) I’m using a 10s Daly BMS for balancing, and a Flipsky smart enhanced antispark on top. Then there’s two Maker X Min-FOC+, a Metr module, mini remote receiver, and a buck converter! The buck converter goes to a sim card based GPS tracker, and a switch that toggles LED lights in the front and back.
Let’s pause and look at where I drilled holes for the power button, charge port, and led switch. Yup, at the front of the deck. That was not intentional, I just fucked up when I was drilling. Since I had space with the NESE modules, I decided to keep them there, and epoxied the buttons in. (This will end up biting me in the ass later.)
Now let’s take a look at the FUCKING SICK led lights this board has!
These are COB LED strips epoxied onto the sides of the deck. I used a ton of rubber bands to achieve this:
Unfortunately, what I didn’t foresee is that when you store your board sitting on the nose, there’s a lot of force pressing down, and the front LED strip got destroyed in days
One thing you might have noticed by now, is how I did the inserts for this deck. I was tired of using the screw-in inserts, so I went with barrels that slide in from the top. Unfortunately the concave of the bottom and top of the deck don’t match, so the inserts don’t sit flush, and the bolts don’t always come out of the enclosure holes perfectly, so some washers end up sitting on the sides, and some bolts are completely missing
Drivetrain issues
- On these mounts you adjust the belt tension using an idler. But this means the other side of the belt can be loose and skip. So I drilled new holes and had Kevin send me some extra idlers. No more skipping
- These mounts hold their angle using friction. They can slide down until the bolts hit the end of the clamp gap. To solve this I drilled new holes in the mounts for new bolts that would already sit at the end of this gap. Now the mounts stay fixed in place. (As you can see though, motor clearance isn’t the best. Motors get smashed going up and down curbs
)
- One of the motors had a faulty temperature sensor. It would occasionally report over 300 degrees C and then that motor would refuse to work. I have a TODO item to add a toggle in vesc tool to ignore temperature sensors, but in the meantime I just unplugged that wire.
- My little brother was starting to grow tall and big, and these hangers were not going to survive in the long run. They were bending.
Remote issues
- The mini remote is just not reliable. My friend who used to use one + this build have had random cutouts with it.
LED issues
- The LEDs would occasionally stop working. I never got to the bottom of it, but based off another build that had this issue, I think the buck converters I’m using have shitty wires that break off when under stress and vibration.
Usability issues
- How do you pick up a reverse-mounted board with no handle at the back? You gotta use two hands and pick up the whole board, it sucks!
- Range was not enough. 10s3p got my brother 15km of range. To successfully complete our group rides you need 15 for the ride + extra to get there and back. So I would have to build a new battery for this board…
Version 2 - TB Direct Drives
I bought a steel Radium hanger for TB direct drives that I had. That + a duck handle should solve the issue with carrying the thing. Front uses a BN220 hanger.
I did a 3-way wheel swap with @Rudi and @RDs to get my hands on some Onsra 115mm rubber airless wheels. (They’re really comfy.) Now this build will really be rideable in the rain + my brother didn’t want pneumatics. Nor could we do that without running into wheelbite issues.
But most importantly – I had to build a new battery. With the buttons in the front, and the back full of electronics, I did not have space for a 12s P42A battery. I could have gone 10s, but I was transitioning my entire board fleet to 12s so that my family didn’t have to pay attention to what chargers we use. So I got busy playing li-ion cell jenga, and I came up with the following layout:
12s4p with 18650 cells This will let me put the enclosure on with butyl tape since no thick gasket will be required. I ordered reclaimed VTC6 cells for cheap, dremelled leftover welds from them, and built the thing:
I’m using an LLT BMS from Apex so that I can monitor the cell voltages / diagnose battery problems. Must have for any board that’s made water-tight with butyl tape, since taking that off SUCKS. Also you’ll notice that I have closed-cell neopreme foam around the battery modules, and beneath them. This is to prevent them from sliding around, and adds another layer of protection. Took a while, but it’s nice
Looking at the insides, the changes this time are:
- No buck converter yet
- ESC is now a MakerX DV6 for more power
- Robogotchi with a Metr GPS module (did not work)
- Flipsky VX1 Pro
- GPS tracker was replaced with an airtag
- Battery is fused
- External panel-mount XT-90 for connecting another battery pack in parallel for INCREASED RANGE
As you can see, I’m routing the sensor wires above the enclosure, because guess what – the connectors were too long so they were touching the direct drives
My friend rode the board to a group ride. Seemed alright, although we ran out of battery at the end. Then I rode it once to test something, and it was a pretty rainy day, and I was still using the jank neopreme foam as the only gasket.
The board thermal throttled on me in 3 minutes time. Later in the city, one motor completely refused to work. I thought I had killed something with water damage, but it turns out the ESC just forgot its motor config. Nice. Also there definitely was a bit of muddy water on the inside when I opened it. Luckily the kapton over the battery caught most of it.
I don’t know what’s up with these drives, but they’ve been nothing but a headache for me since I bought them. I’ll be putting them up for sale later, but for now I knew one thing – I needed another drivetrain swap. Also the VX1 Pro cut out on me on the next ride (had no signal for a whole 5 seconds), so I don’t trust that thing either. Also up for sale soon.
Version 3 - Go expensive
I put a set of Savage TKP trucks on this board. It’s the only drivetrain I had that would give the motors enough clearance so that they’d be finally safe.
The trucks also have a grab-handle, which is AMAZING. I do wish it was just a solid bar without those waves, but whatever. The front wheels also stick out far enough that you can roll the board completely vertical by the handle – very nice
Also I’m running a 15:48 ratio with 330mm belts and there is 0 skipping
I did run into two problems though. One is that the included locknuts were crap and one got stuck, so I ended up unscrewing the whole axle and then destroying the axle to get my wheel back
And another problem is that the clamps for the mounts just slide onto the hanger – the only thing keeping them from sliding out is the grab-handle, but even that doesn’t do a great job since it’s so far away. It hasn’t been an issue yet, but I can slide the mounts outwards and into the pulleys with not that much force, so it does worry me. I think I’ll buy a long M3-rod and bolt the 2 clamps together with it
I also replaced the VX1 Pro with a puck. My brother hates the form factor, but hopefully a poastmote or batwing shell will make him happier.
I modified the antispark switch to have a 10kOhm resistor across the output, because the switch was constantly turning back on after a shutdown on me. Now that problem is fixed
Oh, and I cleaned up the inside of the enclosure of course:
There are a couple of changes I haven’t done yet, but want to mention under this section:
- Replace the barrel inserts with countersunk bolts from the top, and use washers and locknuts on the bottom. Then replace the griptape.
- Get front lights sorted (waiting for Hoyt on that one)
- Wire in the step-down converter for the lights
- Replace the Robogotchi with Metr CAN + SD + GPS
- Replace the airtag with Metr LTE
- Use butyl tape to waterseal the board of course
Conclusion
- Don’t do DIY unless you have a good reason to do so lol.
I wish I had more pictures of the history of this board to share, but my phone died, so here are some beautiful pictures of Autumn in Sigulda from today. This was my first test ride of the board in its current form, and it performed really well, except for the range – I only got 15kms Anyway, enjoy!