Lol i was talking about the spokes specifically, but yeah, all of them 
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Well I kinda dig the sharp look, but yeah, maybe I round it up a bit 
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I love the ambition here. Keen as to see process pics 
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I like the sharper look aswell.
Still think UFO wheels is a better name. 
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I have no problem with the hard corners from aesthetic POV, just that I feel they may be harder to achieve than filleted corners
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Mhm personally I don’t think that this will matter too much. The mold will introduce some rounding on the corners anyway.
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Then go forth and prosper! Super excited for this!
Me too bro 
I’m currently designing the mold, will be at least a 4piece
Small sidenote: I just pumped the tire to 3.5bar (~60PSI) and the hub holds up just fine. I’m gonna leave it in a box for a few days and see if it cracks anywhere.
That reminds me, I could do some high pressure testing when the fist CF rim is done. 
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Nice! you can maybe also test the printed hub by pushing down the inflated tire into the ground, or let it bounce from a height. So you similate some riding forces.
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I dropped it a few times, so far it holds up. If I want to know if it really holds up I’d have to use it a few times though.
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That was a lot more complicated than I anticipated, my respect to people who make molds on the daily. Gonna put it into the printer tonight, and then wait 2 days.
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Do you have any features to properly locate the centre?
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Yeah, two m6 screws though the middle. 
Mind you, this is only the back half of the rim, I’m gonna do the front half tomorrow.
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Guys, I fucked up. I’ve done a blunder. The mould is done, but I forgot to implement compression features. That means instead of hitting the target of 60% fiber, I get a max. of maybe 20% if I’m lucky. Good news is, the new mold is already in the pipeline.
I will try to make a test piece with the new mold, but I’m not so sure that this will work.
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Thanks that’s a nice concise explanation
For Shua: the board moves forwards and backwards with a person on top, for round numbers let’s say 100kg total. So in terms of effort to push forwards you’re right, 100g makes functionally zero difference, that’s why the weight of your VESC and the lunch you had doesn’t make a difference.
But the wheels don’t just move forward (linear motion), they spin (rotational). What shutter said above is that every movement requires the wheels to spin up, and fight against their rotational inertia due to the weight just of the wheel. The wheels don’t weigh 100kg, they weigh maybe 200-500g, so any reduction in weight their makes a much much bigger difference. To get a “feel” for this you can try hand spinning an 85mm urethane wheel for a 200mm pneumatic, or turning a bicycle upside down and spinning a big mountain bike tire in open air vs a kids bike or a racer.
As the others said I also don’t know specifically what percentage difference it makes though.
Soz @Linesflag this is related to the design and purpose of the wheel so hopefully not off topic
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Have you thought what sort of testing you’ll do before releasing these to the wild?
If it were me, I’d aim for ~2x safety factor as a catch all. So
- crank a tube up to ~100psi and let it sit for a day or two
- figure out a way to load up one rim with ~20lbs of “board weight” straight down. maybe with and without a tube+tire.
- try to pull the tube+tire off sideways to do some sort of shear force test on the sidewall to simulate aggressive turns
- could do a ‘drop test’ but i think the tube+tire are going to spread the load evenly enough that this wouldn’t be a useful test
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Np, I already gave him a similar explanation too.
I haven’t yet planned anything specific, but I will definitely do a high pressure test (up to 130PSI/9bar), and also actual riding with them. If I ever try to sell these I will probably also make a set for someone who is an avid offroad rider and gather their feedback.
The 3dp rim is sitting on a shelf at 60PSI for a few days now, so far it holds up just fine. But the rim is also 3mm thick with a generous fillet, so expect it to withstand a higher pressure than normal rims, f.e. trampa hypa.
