I wanted to share my build. This is the first custom board I have built and my first time experimenting with a project like this; much of the inspiration has come from previous builds posted on these forums so I figured I would contribute and put mine out there as well!
Lazy Dog Warehouse Neoprene Sponge Foam Rubber Sheet Rolls 1/4in
25ft - 1/2 inch PET Expandable Braided Sleeving
4 Way Electrical Junction Box, La Vane IP68 Waterproof 4 Way Cable Connector
The battery enclosure is a waterproof electrical junction box that has been plasti-dipped on the exterior/interior. I made two holes in the side of the box and used two cable gland joints to pass the wires through towards the rear of the board. The box is padded with foam that is glued to the inside and then the LiPos are wired in series to get 12S/12Ah. XT90 connectors were used to link the custom wiring to the battery set up and I wired a battery capacity tester over the batteries in series to get a rough idea of remaining battery life.
I put the junction box in the center of the board and drilled holes dead in the middle of the board to mount the box by the very center to make sure board flex was not going to be a problem. I put foam padding underneath the junction box to try and dampen vibration and make the contact between the board and the box more uniform.
The FSESC was mounted in another plasti-dipped junction box using velcro to secure it on top of a foam pad in the junction box. The battery power wires also force it down so hopefully it does not come loose. I am a bit worried about thermals since the heatsink of the FSESC is not directly mated to any metal/conductor and there is no airflow in the junction box.
I will see how hot the setup gets and possibly add fans for forced air cooling. The FSESC has a built in anti-spark switch which I housed inside another 1" cable gland joint and rigged it coming out the exterior of the junction box for a nice"on/off" switch.
Another two 1" cable gland joints are used on the back of the junction box the thread out the motor power/sensor wires from the box. This junction box was raised off the back of the board using rubber door stoppers that are velcroed to the board and then further secured using screws/nuts through the deck. This was to prevent vibration and angle the junction box away from the motors.
The motors are mounted using the e-toxx dual chain drive kit in 8-40 gearing. The motors were ordered custom from alibaba to get the 150kV. I used a mixture of braided sleeving, heat shrink tubing, and wire looms to cover/waterproof the wires throughout the rig and prevent them from being damaged. The whole electrical system is sealed and the connectors are filled with silicon to waterproof the wire inlets so this should be very weatherproof. I have mounted a go-pro mount on the front of the board which accepts a wide variety of battery powered LED lights. I had good luck finding a lot of compatible lights marketed as “underwater go pro LED”.
Congrats on your build! I am looking forward to finishing mine using the E-TOXX chain drive too. What is the reason you didn’t mount the top bracket, space constraints? Can’t tell from the pictures.
Yep, with the current set up the overhang from my back enclosure would impact the top bracket. It only has a few milimeters of clearance right now when the trucks are turned fully. I’d like to modify it in the future to trim some of the rubber from the riser and add on the third bracket. Seems like for MBS decks and MBS trucks the e-toxx chain drive is really tight but it does work.
Thanks, and definitely - I live in northern Indiana and the snow can get really crazy here due to the great lakes. Where I park is about a 20 min walk away from where I work so I am hoping when things start getting crazy outside I will be able to rip it no problem. Also can’t wait to hit some trails when the weather starts to warm up here.
Sweet build! Looks kinda ghetto with the see-through plexi-glass but like it gets the job done, looks real solid! Got pics with the headlights turned on?
lmao it is definitely ghetto. Tbh personally I like the look of being able to see the electronics through the plexi, and it is also functional if you are trying to monitor your battery/esc status. I’ll try to get some pics with the headlights on tonight. My 9" mbs wheels/hubs are supposed to come tonight so I think I’m gonna switch out my back tires to 9" tonight as well - we will see how that goes.
I added 9" tires in the back, as well as the third motor mounting bracket. I also removed the rubber rise pads and mated the back FSESC junction box flat against the tail of the board. Seems to be working fine as far as clearance goes with the brackets.
The 9" tires in the back make this thing look like a real beast.
Just got back from my first long ride. Got up to 28 mph top speed and there was still a bit more left on the throttle but I had to back off due to speed wobble. I have MBS orange brushings and I could go stiffer, but I love how carvy they are so I think I will stick with them. Besides, going 30 mph is already scary to me
As for battery life, the 12s 12Ah LiPo setup did just over 10 miles before I called it quits. I was at 3.7 volts on my lowest cell so I probably still had a mile left of possible range without going danger mode. Pretty good range for only $200 of battery IMO. We will see how their durability is with charging over time.
Is 3.7 the resting voltage (after ~10 minutes or more) or directly after ride? In my opinion you can go down to 3.5v safely, it will rebound to ~3.7 resting voltage, which is totally fine. At 3.7v you are far from danger zone, you are more like in comfort-longevity zone
15c on 12Ah is ok especially because those are graphens and they hold up to there specs usually. Wouldn’t go with the blue turnigy lipos @12Ah and 15c thou.
Some guys where riding even the 8Ah version of those graphens with a good result, but they also where done after one season riding.
I have not had issues with the “12c” turnigy lipos. Not that I’m pulling any crazy amps from em though. Will see how they hold up after more time.
Definitely should be treated with care of you want em to last like any lipo, especially cheap ones.
cool…but i’m even more confused about the c rating now 144 amps? what are safe settings for 190Kv 15/60t 152mm wheel size belt drive setup…using these batteries
This has been my experience as well. I’ve got each of my motors at 70amps and ripping it full throttle barely makes the batteries heat up. I have 4 of the cheap blue 12Ah ones and I really like them, seems like they have no issue pumping massive power. Not sure how they will be from a longevity standpoint though…