Realistically, if I just want to cruise around the neighborhood, I could put something together with the amounts of spare parts I have, only battery that is lacking, I have a old 10S3P made from NCR18650B, not capable of much current, but doable, would have to rebuild it, and last time I looked one of the cells appeared to be a bit rusted, it’s been sitting on a shelve for more than two years
First it was a 6S4P, and after that with a few new cells, a 10S3P
Time to bring this board back since I miss riding on thane
Jus putting together whatever left over parts I have, it will be a funny combination of parts. Weak 10S3P made of NCR GA with more cycles than I know to count? Check. Aliexpress 6355 motors that cost $25 each? Check. Titanium motor pulleys? Check. StormCore 100D? Check
This is at least for now. Nice thing is that with the StormCore, the Hummie deck should fit 10S5P of 2170 cells with barely any room to spare for wiring, a receiver and a FlexiBMS, this with my slightly routed deck. With Samsung 50E this mean 875 Wh and 70 to 100 km range, double stacking make it even more appealing
First step is to make yet another revision of my press fit 3D printed pulleys. The failure of the previous revisions is that the steel pins doesn’t glue well to the ABS and it end up sliding and touching the mounts. To remedy that I did a few grooves for the glue to to hold on and will do somthing similar on the pins with a Dremel
Actually it’s pretty simple to make this pattern, make a swept triangle cut and add torsion to it, pattern this a few times around the hole, do another one with the angle to the other side and also pattern that the same amount of times, and finally make a another pattern to propagate it to all 5 holes
Definitely worth, I must have between 2000 and 3000 km on it, has a few cracks that I super glued, others that couldn’t be fixed and a lot of scratches due to the board being so low. Overall it held up well, but regular ABS is not the material for it, need something stronger, more flexible and less subject to layer separation, ideally I would like to print it in one piece in something like nylon PA11, but way too expensive
I would also make some design changes, thicker walls, maybe change the screw location to eliminate the cracking problem, wouldn’t look as cool thought
Thinking of printing it in two pieces, have access to a big printer, and making a mould out of the print, then vacuumbag some CF. Have a kit for the mouldprocess ready to go.
That would be cool, I bet if I had made the design more smooth in the corner, a layer of CF or even glass fiber would have made it last forever, but having the sharp design feature may not work
Those titanium pulleys do look sexy, the motor shaft is a bit short but I think it’s good being 10 mm, plus set screws and retaining compound
Now to the battery pack, have to disassemble my ebike one
Now I’m thinking if I do a top mounted external pack that can also be used as range extender for the mountainboard or inside the enclosure. I still have an old 10S3P that I can use as the extender, one cell is badly corroded so I’m a bit afraid of messing with it, could make a 10S2P with it, but then I don’t have how to charge it
Keeping the build theme, the battery is done, capable of massive 30 A discharge, so I had to take precautions and use a 10 AWG wire, but only outside, connecting the P groups is a 16 AWG, and off course a 30 A fuse
Also in one half the P groups are held to each other using double sided tape as a test, it isn’t strong but provides good isolation, the heat shrink holds it together
And after quite a while of chiseling and sanding all the silicone that held the old battery is removed so the double sided tape can stick to the wood, could have used silicone again but that takes too long to cure and I want to test ride tomorrow, still need to do a pice that will house the switch and the charge port on the top of the rear truck
The BMS is one that I bought at least 3 years ago and never used, hope of works, the battery is quite unbalanced since it was split in one 6S in my ebike and one 4S for a test board, so they are 3.83 V and 3.72 V respectively, I could have balanced manually but would take too much time
Quick as always, just a month latter, here we go, all in place with Dual Lock, need to make some 3D printed guides to run the wire in the side of the deck
Should have around 70 km of range, will see if I can test next weekend
Some testing for the Iron Foot challenge, looks like the sweet spot is around 20 km/h, quite windy today so it might skewed the results a bit, and also the ESC measurements not being that reliable
I known can do 38 km with chill riding on this board, so maybe 65 to 70 km with the range extender
