Well, after more than 3 years collecting dust, the time has come to finalise this project… Idea is to make a decent 4WD off road eMTB. It will be black and white themed with custom enclosure, some lights and of course as clean aesthetically as possible.
What I have:
APEX Predator Deck
MBS F5 Toe + Heel
APEX Air trucks
APEX 12s6p battery
2x Stormcore 60D+
4x Flipsky 6374 140kV
Moon Drives - Helical
MBS FiveStar
MBS 9" Tires
Voyage Minnie (just purchased)
Hoyt Puck
Enclosure is almost done, I did a first 3D Print, all looks good, so the next print will be final.
Now to the questions:
It’s been a while… 3 years in eSkate world have passed, many things have changed, I see a lot of companies do not exist anymore (Apex, Moon Drives, Hoyt…), so, since I am planning using parts listed, is there anything I am missing in terms of known cons to the specific part? Is there anything better now available?
I never did a 4WD board before, so I am a bit worried regarding CAN bus connection of the whole thing. How should I approach connecting everything together? I read that for connecting 2 VESCs via CAN one should only use CANL and CANH pins? but how to connect Minnie then? Should i go Stormcore > Minnie CAN1> Minnie CAN2 > Stormcore2 or there is a better solution?
Anyways, long road ahead, there will be a lot of printing, routing, skinning, light installation, painting etc… But I am feeling really happy doing this once again.
As far as CANbus, you can have all devices in a daisy chain and they will all be able to see eachother. Because it’s a bus topology architecture (the bus part of CANbus) the H and L lines can simply be tapped into at any point.
A good way to visualize this is looking at the traces on the back of your Minnie PCB. You’ll notice that the 2 CANbus ports are linked. Each device on the CANbus gets a unique CANID and either sends or recieves data based on it’s ID and not it’s physical placement in the network.
Far far simpler communication protocol than UART which requires mux and de-muxing for multiple devices to share a single connection. (Eg. USplit)
The Puck2 is available (from mboards ) and is a significant improvement over the original Puck. USB-C, hall sensor, better resolution, much more physically robust.
Puck1 is still as fine as it’s always been. Just gotta be aware of the potentiometer issues.
Just wanted to add, I built a 4WD board with 2 Stormcore 60D+'s connected by CAN, and powering them on and off in sync has been not straightforward.
My first attempt was connecting the Stormcores together in all 4 CANBUS pins (+5V, CANH, CANL, and GND) and a power button connected to one ESC. It resulted in a bizarre behavior where I could not turn them off. If I switched off the powered button, the ESC connected to the power button would turn off for a millisecond, but the other one would stay on and power on its neighbor ESC right back on. It looks like either one of them being powered on forces the other one to power on or remain on.
My second attempt was connecting the ESCs by only CANH and CANL. Then the second ESC without the power button would not turn on unless you used the roll-to-start function. At this point I just installed the second power button to the second ESC, so now I have two power buttons on my enclosure.
Now, I power on both ESCs by pressing both power buttons. However, I just have to turn off power switch off and the other will power off too.
Great info, 2 power buttons are not end of the world, I would have to have them both anyway if I stick with the plan of using 2 Apex stormcore enclosures since there are pre drilled holes for them…
This way I could leave both stormcores inside the enclosure between my legs. Also it saves weight of 2 APEX stormcore enclosures, and of course it looks a LOT cleaner
Also please tag anyone who could chime in on this matter.
I don’t recommend shit on top of decks, but electrically, long phase wires don’t matter very much if at all. Just make sure the wire size is large enough to not add too much resistance. Long battery wires are bad. Mechanically, I don’t know if tinned braid would survive repeated flexing or be as resistant to cycle fatigue as silicone-insulated high-strand-count copper wire, which is what I would probably choose.
So about long wires. Running long wires means there will be some unwanted inductance in the circuit - on the motor side this doesn’t matter, because the motor has huge inductance by comparison. On the battery side this matters, the input capacitors on the ESC are there to get rid of the inductance of long battery wires. If you have too long wires battery side, the input caps on the ESC will be insufficient. In some other hobbies people add extra capacitor banks right before the ESC if they run longer than ideal battery wires.
Also having the ESCs in the middle can yield a much cleaner look, less weight, and that weight is more centered in the middle which is also better than the weight being on the far ends of the board.
I personally don’t think braid is good idea, we stopped using braid in flexible packs due to it sometimes cracking over time.
I’d either route space for the wires under your feet with a router (or a dremel with a 3d printed router attachment), or run footpads that have space for the wires.
You can take some cable management inspiration from my mountainboard “JumpBro”, or it’s earlier iteration “RaceBro”, though be warned the build thread is quite long for that, but the RaceBro part is only the beginning.
The wires exit the pelican then they go into a fairly stiff foam footpad, then they are routed under a 3d printed trampa style cable cover. On RaceBro where I couldn’t have the motor wires exit directly towards the hanger, I run them upwards and directly into the 3d printed cable cover. On JumpBro, I ran them towards the hanger, secured them to the hanger with zipties, then distributed them to the two sides of the baseplate and run them up through a hole in the deck inspired by @Shadowfax 's 4wd lacroix.
In the RaceBoi iteration you can also see how nicely I made two dual ESCs fit under the battery in a pelican storm im2050. That’s in the same thread as the RaceBro around the third of the thread I think. I can link the pictures to all this if you ping me later today
) and is a significant improvement over the original Puck. USB-C, hall sensor, better resolution, much more physically robust.
