I keep changing plans for how I wanna build a race board and have ended up with a bunch of extra equipment. Buy it so that I can get it out of my apartment, and purchase more stuff that I will also later decide to discard due to a lack of foresight.
Parts are new and unused unless noted. Prices listed include USPS shipping to US main 48 unless noted. Asking price is what I originally paid for them, so I’m expecting to sell at lower prices and with quantity discounts. Make your offers, cuz I want to move these!
CST 8x3.5 - 4 tires
Lawnmower tires of the same type that @Dinnye originally ran on his raceboi build. Comes with tubes if bought before the other tire set. Price (USD): $20 each, lot of 4
Kenda 8x3.5 - 4 tires
Tested to have 20% more grip than the CST’s on the bench, unconfirmed IRL. Has narrower rim beads than the CST’s, and would benefit from smaller spacers. Comes with tubes if bought before the other tire set. Price (USD): $20 each, lot of 4
12V LED bars
5mm wide, 750mm long, sticky back, PCB mounted LED bars. Lights up fine from 9V thru 12V. Divides into groups of 3, which can be rewired in series to handle high voltages. Hella bright. 6 available, @stan_he already has dibs on at least one. Price (USD): $5 per bar + shipping, 6 available
24V RGBW COB LEDs
12mm wide COB tape with RGB+5000K white channels. Analog, and lights up anywhere from 24V down to 6V (but it’s pretty dim by that point). Has a conformal coating for water resistance, which must be carefully scraped off the contacts to solder. See this website for specs. May have minor creases from transport but are otherwise new and un-used. Lengths are approximate and vary slightly between strands. 4 lots available:
Mod 1.5 open gear drive stuff to come, once I figure out heat treatment. I got laser cut gears and then changed my intended wheel size (requiring larger gears), but don’t want to pass along gears with annealed teeth.
Thought I could get em hot enough for a quench with a couple torches, but they didn’t have enough juice. After further research, the alloy also needs to spend a substantial amount of time at high temperature for tempering, so it sounds like an electric kiln is the only way to do it properly. Odds are good that I can talk my boss into getting one for the shop I work at. If not, I’ll buy the cheapest viable one and delude myself into thinking that I’m still saving money.
The procedure will be to bring them up to bright red 850C, oil quench, and an hour at 500C or so to temper. That creates high toughness and about 35RC harness, which is…meh? I could try 1045 steel in the future, but that’s the only other hardenable option I’ve seen that’s not something real expensive like AR500. Professionally made gears have fancy surface treatments that apparently reach 50-60RC at the surface with a softer, tough core, but that’s not in the cards for homemade.
My local heat treat place charges $250 minimum to do hardening, and it doesn’t reach full economy of scale till I hit 200lbs/90kg of material. I’d have to find a much cheaper place for that to make sense, or do a group buy with 30 other people.
My thinking was that if I could get the unit cost of the gears as cheap as possible, I would get longer lifespans just by making large diameter/tooth count gears, and I wouldn’t mind replacing them once a year or something.
When I order gears for the 10" go kart wheels, I could totally put out feelers for a group buy. The prices come down a lot if I get around 10 units or more
Interested to hear about your experiences with them once you try it. My first CST set is still going strong, but I went through the set of rims completely that they were mounted on so not using them atm. Not my first track tire choice, but I still love them for hard carving on my secondary board. They would definitely be fun on Nothing Fancy.
