Building stealthy eSkateboards from regular skateboard decks | N.E.S.E | CF integrated enclosure | different hub motors

[visnu777]

Hi there, this spring a friend of mine I haven’t seen for a while told me that he is driving around over there with an electric skateboard going 45 kph with a range of 35km. I immediately got hook up on the idea of driving around and getting more independent from bus schedules. I don’t have a car but use public transport a lot so it had to be small enough to carry around. I wanted to use my old Element Jeremy Wray deck which I recently transformed into a cruiser board with 3d printed TPU riserpads and longboard wheels. It should be able to be used like a unmotorized skateboard in case police gets suspicious or power runs out. I did a quick search and ended up ordering a cheap 70mm hub motor kit on ebay, sold by a absolutely clueless seller :D.

In the picture I already installed a 3d printed PU (from TPU). I ordered a custom 10S4P Battery made of Samsung 25R cells from someone building these professionally (including BMS) and when it arrived I could not wait to try it out and taped everything together for a test run. During this test run I encountered strange behaviour: In slow mode, everything was fine, but seriously, who wants to use that apart from getting used to driving? In medium mode there was random stuttering in between but it was mostly usable but in fast mode I had stuttering, immediate full throttle and stuff like that so something was obviously wrong. During that time I started doing research over here btw, which helped me pin down the problem. It had to be the ESC so I ordered one from diyeboard which worked perfectly. I taped everything together and already had a lot of fun when after one bigger trip with my girlfriend one motor started scrubbing at the magnets. I’ll never buy cheap stuff from ebay again Now I was already hooked up 100% so I had to get replacement hubs. I ordered the 70mm hub kit from diyeboard but when It arrived it revealed a bit of a problem: They are longboard style trucks but everything I already planned was based on regular trucks. (The ebay hubs were Maytech style so I cut my trucks the way the hubs fit with their rectangular shaft) The new trucks made turning way too sensitive so I had to move them one hole-distance each apart.

Now I was in love with this hobby: The new motors were so quiet and powerful, speed was a little lower (25kph compared to 28kph with the previous ones) but it felt so much better, perfect Time for the casing… At work I had the opportunity to get the deck laserscanned with high precision:

I designed a case perfectly aligned to match the board shape for 3d-printing:

but my printer is way too small so I had to depend on others… I hate it the printers at work were all not operable so I had to think of alternatives. I almost bought a CR-10 5S with 50cm build space. With that one I could print it in one piece but it would have been a waste of money since I mostly print smaller parts which can be done better with the fab mini. This forum finally gave me the solution: Kydex. I read a bit and after that I ordered a 30x60cm piece. The delivery gods were angry at me so I waited 3 weeks for it after which the seller did some research after which it was back on track. In the meantime I ordered another one to get the case started but with this there was some delay too Like there was a grudge on my whole project While waiting I worked on the lights:

They are driven by the main battery, I found a LED driver with up to 56V input and 350mA output. They’re still a work in progress (right now I don’t have them assembled to the deck at all, I have to redo them first)

After working on the lights I started modelling a bed for the batteries since the board has strong concave that needs to be corrected so the batteries won’t stretch. I printed it in 8 pieces on my fab mini with TPU and puzzled them back together.

When the kydex arrived I already had a wooden body prepared for it:

So i could start immediately when the delivery guy came by I placed a thermotransfer pad between ESC and the aluminium heatsink plus I added a real heatsink on top of it. The plan was to cut a hole in the case for the real heatsink and make the surrounding area waterproof.

This V1 build worked like a charm until the board broke. It looked like swiss cheese all over so when I accidentally hit a really evil edge it cracked RIP my old friend After that I instantly ordered a new deck (Sale, glas fiber coated) and tried to transfer everything to it but I wasn’t aware of the non standardized truck distance. I was in a hurry and did a really dirty job to get it running at all costs so after that one I ordered a new deck to do it once again right

The green deck is for my upcoming project, its still a regular deck but slightly larger (33.5x8.5 inch). I’ll countersink(?) a battery and electronics bed and cover the whole thing with carbon. The shape will also be changed slightly depending on the new 90mm hub motor trucks (this time with replaceable pus).

Thanks for watching, Michael

[DAddYE]

How tick is your kydex? Did you use a heat gun?

[chrisongtj]

Looks like a really decent job on the Kydex. Im also curious to know how thick it is?

[visnu777]

Thanks It is 2mm Kydex, I put it in the oven at 150°C for some minutes until it was elastic and then I tried to put it on the wooden model for the case, after which I immediately put some foam on top and started pressing everything down. This resulted in a raw form that was perfected afterwards with a heat gun (Heatgun, foam, press and repeat*n). You might have noticed the texture difference between the two parts, the battery part went much smother since I let it in the oven for a shorter time than the electronics case which had obviously too much.

[lowGuido]

I threw this together one friday night cause I wanted to skate on the weekend.

[Alex.Scheff]

What type of esc is this?

[visnu777]

Not bad for quick and dirty, nice I got my new 90mm hub drive with replaceable pu and took it for a testride looked a bit ridiculous (eDragster ) The additional power and diameter work out as expected, they have better speed and torque at the cost of size and weight. Lets hope I’ll still be able to carry it around like the previous one, otherwise I’ll get the new 75mm hub motor from diye and build another version with the smaller deck (also with carbon fiber this time) @Alex.Scheff I’m pretty sure you asked Guido but just in case you meant me: Its a diyeboard esc V1.1 with an additional heatsink to have it stand out of the case for cooling but sealed off properly.

[Vanarian]

This is something we should see more often, nice job ! Which width are your truck, standard 180mm ? Did you put risers to counter wheelbite with the RKP trucks ?

[visnu777]

Again, not sure if you adress me but nonetheless: The trucks on the pictures are 6 inch, since I moved them outwards I had to print a PETG riser leveling out the contour (using the laser scanned model) plus a TPU shockpad for vibrations (and some height)

[visnu777]

A little update on my chaotic planning and constructing:

I have to start with the plan changer: My DIYeboard ESC is half dead. I drove quite steep roads and at some point torque was gone. I stopped and checked everything and saw that one motor didnt work any more. I tried to fix it / find the problem but no chance, I carried it home. Maybe I’ve stressed it too much but It should have survived it. One motor channel is dead. I almost ordered another one when I said to myself: No, you will buy two VESCs now, at least you can do lots more with them (interfaces etc. I plan to build brake lights first). I ordered two Flipsky FS ESCs.

I recently bought 30 VTC 6 cells, 10 N.E.S.E. packs for 3P and build another battery.

I sold my 3 month old 10s4p pack to a friend. The new pack will have no BMS (at least for now, I ordered one in China but I’m not sure if I will use one this time. The VTC6 should be stable according my research on the web. With this cells I’ll have almost the same capacity as with my old 10s4p with Samsung 25R but save some weight. I enjoyed the 90mm hub drive a lot so far so I want to use only it exclusively and build the one eboard for me. As I told you before I’ll use a 33.5x8.5 inch regular skate deck (Minilogo). I’ll move the trucks further apart so the wheels will have enough space. I already tested this without electronics and it feels really good, like on railroad tracks . Yesterday I cut too much from the deck on the previous pictures and had to order another one. They’re quite cheap but its a waste Next time I’ll be more careful.

Btw, I got 195mm Paris trucks for the front

[visnu777]

Under construction:

Still a long way to go but you can see where its going Its getting quite crowded in the electronics cabinet, I’ll have to be creative I have 2 Flipsky FSESCs (VESC 4.12), a Receiver for the remote, a Bluetooth module, an ESP32 MCU, a gyroscope, a led driver and a step down converter for 4x USB power.

[sunnyD]

Teamgee better be taking some notes!

[visnu777]

Some more dremeling, filled up the gaps, sanded it down, cleaned with acetone.

the lower part will be covered with carbon fiber two times, first I’ll start at the top and fold it to the bottom and then I do the second layer only covering the bottom. I have no experience with CF so far but watched a lot of tutorials and I’m feeling pretty confident that it will work out, both the laminating process and the final board stiffness. If it doesn’t I’ll try something like the guys with the Spud CF decks, using the router to create a flat area for the batteries and electronics and then put a case on top of it. But I want this one to work out, making everything accessible from the top is way cooler than the usual bottom mounting of cases Since I’ll make two lids I’ll lock the battery with screws and the smaller electronics compartment gets a quicker locking mechanism so I can easily access the stuff inside. Since I don’t want anything to be visible on the outside I’ll hide it there

[visnu777]

so far so good Its far from perfect but somehow I made it. The first carbon fiber layer is attached to the top side of the deck and in a vacuum bag. (I hope It will not stick to the bag too much tomorrow.) I will add one more cf layer on this side but only covering the flat outer areas (mostly for decoration). The lower side will have one layer covering all and then at least two layers in the middle around 10cm wide for further stability.

[visnu777]

My mess:

I can’t wait to tidy up again, the project totally blocked my VR-area

[visnu777]

Time for a test drive when I come back from work. I have to sand it down once more and do a final epoxy coating after that test to seal the truck holes. I’m not sure about the clear coat yet, I have it here but it takes forever to dry and the epoxy is quite shiny all by itself. Is there any benefit out of it besides UV protection?

[pat.speed]

Looks great, I’m thinking of a similar shortboard build. The clear coat will help with protection from scratches and rocks, and it’ll make it even more glossy

[visnu777]

Thanks I’ll do it when its rainy outside

[visnu777]

I just did a test run as planned and WOW, HOLY SHIT! I have to make the VESCs much smoother, right now its a beast My CF-Wood construction seems to hold up perfectly as far as i can tell right now (hurray :D)

[visnu777]

My frist “real” testrun was successful and I was happy but when I returned home I wanted to check the remaining capacity. When I plugged in the antispark the electronics compartment started to smoke. After disconnecting the antispark I saw that the USB-Port had contact with the carbon case and melted. When I checked both vescs seperately both were unable to connect to the vesc tool so I must have destroyed them. The cause was a worn down shrink tube at the connection between the two 5s3p halfs, it made contact with the hull resulting in 17V on the USB…