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Fast Cruiser | TGM 36" Kicktail | Caliber I 44 | DIY 6355 230kV | DIY v4 mount | 12s3p LG HG2 | DIY VESC | 83mm Flywheels


#1

So it was back in May that I stumbled upon this website and boy what a fun journey it has been. I’ve been longboarding semi-seriously for about 3 years now and I am very comfortable on a board at medium speeds (25-35mph). I knew about the Boosted Board and others a few months before I found the forum but at $1000+ for the specs they have just wasn’t worth it to me. I want to be able to sustain 25mph easily and hit 35mph (or more!) on occasion with decent range.

So after almost 2 months of studying this place this is what I’ve come up with:

Parts List:
36.5" 9 ply maple with bamboo inlay
Caliber I 44 degree trucks
83mm Flywheel clones w/ ABEC 7 bearings
Custom 1/8 aluminum risers + voltage display mount
DIYES 6355 230kV motor
DIYES VESC v4.12
DIYES 16/36T motor/wheel pulley kit
12mm HTD5 belt
(36) LG HG2 3000mah 18650 cells in 12s3p configuration
Custom 1/8" ABS enclosure
Psychotiller motor mount -----> DIYES v4 motor mount
Winning Nano remote 2.4 ghz
(2) iMax B6 chargers

The right one is for the front truck for the voltage display that I will eventually put on. I did have one and it worked good at 6s testing the VESC. Tried to hook it up to 12s not knowing the one positive can only handle 30V…oops. Sparks and smoke was emitted. Lol

Vacuum former, made with some scrap 3/4" MDF. 16"x18" vacuum area

Isn’t perfect, but neither was my mold. I’m satisfied for a first attempt.

I did the battery a little uniquely. I made two 6s3p packs and ran them in series for a 12s3p pack. 44.4V * 9Ah = 400Wh. I have the battery max on the VESC set at 40A so each parallel pack sees 40/3 = 13.3 A. No BMS. I connected an extra (+) to one battery and an extra (-) to the other. So I have 2 positive wires on one battery, and 2 negative on the other. One set goes to the VESC and the other pair is mounted on the enclosure for individual charging at 6s with two iMax B6’s. I just made a short jumper to series connect for 12s while riding. A little cumbersome, but I’ll live with it.

Moment of truth! First charge.

Getting everything in position. I wrapped the batteries in some felt, sealed them up, and velcroed them to the enclosure.

Balance connectors and 2 sets of (+) and (-) connectors glued in place. XT90S also located outside as the master switch.

Charging connections closeup.

Recorded Top Speed: 32.3 mph

The board is currently out of commission because my psychotiller mount broke. I think I was partially to blame, I looked at it one day before a ride and the alignment of the mount/belt looked off. I gave the mount a small push to see if it was loose/cocked, and it snapped. I just could not get that thing tight for the life of me, I even welded together 2 spacers out of nickel strip to try and snug it up before tightening. I used red loctite on everything too. Wasn’t a huge fan of the mount TBH. The truck clamp needs to be wider, fit more snug, and have a wider slot that closes when you tighten it. I have a DIYES v4 mount on the way that looks to be what I think will work better.

I don’t know if I’ll continue this in this thread but this is my next project. Laptop 18650 battery pack. I’m thinking of a 10s8-10p build, so 80-100 cells. I figure if I set the VESC battery max at 40A @ 8p each cell will only see 5A, which I think is manageable for these cells. Looking to use only cells that are 1800+mah.


#2

Nice small build, interesting battery setup :slight_smile:

12S @ 230kV @ 16/36 sounds crazy, please don´t forget your helmet.


#3

I almost have what I think to be enough laptop 18650’s and I’m planning how (or even if) I’m going to do this. I made the enclosure already, which turned out much nicer than my first one! It is about as big an enclosure I can fit without going thicker.

I hit the jackpot on some really good cells that are 2200-2400mah each. Specifically they are these cells:

So here’s my theory: I can nice and snugly lay 50 cells in my enclosure and it’s thick enough to go two packs high. So I can fit a max of 100 cells. If I make two 5s10p packs and connect them in series I’ll have a 10s setup. I’ll set the battery max on the VESC to 40A at most (maybe less). Running a 10p pack that would mean each 18650 has to deliver 4A continuously at max. The Samsung 28A has a max continuous discharge of 5.6A.

Setting the VESC battery cutoff at 3.4V per cell, this graph says I should get 1250mah out of each cell per discharge assuming a 4A load (my white line). Works out to 450 watt hours.


I have also considered a 6s setup with something like 16-18 in parallel. That would bring the load down to like 2.5A per cell.

How do you think this might work?