Dang that is cheap! I’ll have to check their EU selection.
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Awesome thanks man! I’m just gonna play with them, I’ll post my results here, along with any changes etc. Won’t publish them elsewhere.
I’ve been making high SFPM contact wheels for metal abrasive belt grinding using solid higher durometer TPU with excellent results, so that’s where I’m going with this. I think there’s a sort of “oh it’s “flexible” so obviously that wont work” preconception about TPU, but if the right material is used, at 100% infill, it’s stiff enough to be structural, but will outperform most other polymers in durability because of the insane layer adhesion and having just enough flexibility for extreme forces to still be within the elastic deformation range.
Every one of the contact wheels I’ve made have been exceeding cast PU in both temperature and tear performance, destruction testing almost never failing on layer lines when the print setup is right.
May not work for the wheels (although tires obviously a possibility) without some geometry tweaking, but I’ve already been testing some PU printed drive gears with excellent results thus far.
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What’s the filament consumption for these? Mbs wheels aren’t exactly expensive at 15$ a piece, but I too do love to diy and print things just because I can.
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I have this idea kinda stuck in my head now to make a CNC lathe designed expressly to finish machining wheel hubs that may have been printed. The goal would be to take them to very specific dimensions so they could be fiberglassed then the same machine would finish the dimensions again after the fiberglassing step.
The reason making a CNC machine for this job makes sense is the size of wheel hubs we use, even on the largest end like a 6" x 6 go kart hub is still fairly small even compared to the 3D printer that would have printed the parts that will be machined on it. Small size = short linear rails = affordable. Also the main rotation would be powered by a regular Esk8 parts.
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I haven’t read the whole thread, but an early prototype (the second one to explode) massed about 210 grams all bolted together with no bearings.
A few percent of that is the bolts, but let’s round it to say 200 grams per wheel.
A nice roll of filament runs between $20 and $50+ per kilo, so that’s five wheels per spool, or between $4 and $10+ per wheel.
If you used CF-nylon or something else more exotic that could increase the price to $20/wheel or more.
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Currently printing the rims after getting the new filament yesterday.
I wouldn’t bother too much with the very early prototypes, as they weren’t sturdy enough to survive just pressure pump up.
The 8" rims were roughly 4 complete rims per 1kg PLA spool with 100% infill and the 10" rims are 2 complete rims from 1kg PLA spool.
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Im sure somewhere close to you should be a maschine shop that could do this for you for very little $ on a proper lathe
Easier to pay 50$ than to build a lathe haha
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as much as I know there are far superior ways to reach the end goal of having many wheel hubs, ie all the ones I would want are available online already. Reaching the goal by making a small CNC machine that makes wheel hubs is an attractive option. Makes a lot of other things like in particular parts for the slip ring on the leiftech/SBX.
ah well shit the machine shop could make those parts too. Well I’ll be damned.
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I mean if your planning on using it more than once or twice, it may be worth it for the fun of diy 
I keep liking diy less and less and just want finished products from the start as college takes up all my time and energy 
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Finally got the rims finished for three other corners so I can probably go for a test ride tomorrow to see how they feel.
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Comparison between the 8" and 10" wheels
Note, the wheel pulleys on the 10" are 70T and the ones on the 8" are 68T. Check the height from the bottom of the pulley to the floor.
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Well I’m back from the first test ride and didn’t die, nor did I have to pull my wagon home, so a success I suppose.
Couple notable ride feel related changes.
-
Cons:
Man the torque is down, but this was to be expected, the pulley ratio + wheel size increase does reduce the mechanical advantage, so there’s just less torqyness(?) from that, but I also feel that the bigger+heavier wheels added with the bigger+heavier rims have added a lot more tire inertia, so it takes more torque to get and stop those things rotating. Otherwise carving felt still good and not too tippy. -
Pros
Maaaaaan is it smooth though. I even did a bit of off-roading and all the roughness I had compared to the 8" were just gone, especially when hitting the larger stone sized gravel. Very happy on that end. Tarmac was basically silk.
I didn’t do a good run to get a good comparison for efficiency, but I think the afternoon ride will be better for that. I’ll present some numbers on the results between the 8" and 10" setups. I think this setup is much more of a GT (grand tour) suitable, just due to the smoothness, but I want to test the efficiency, as I’m interested if my hypothesis about the motor loading holds water in practice.
Couple mechanical notes.
rear-left motor axle’s tip very slightly rubs on the tire
Slightly tightened the front truck in the middle of the drive just to get the feel a bit more damped at speed. Need to do the same thing to the back… but otherwise I didn’t really have any notable tire vibration/resonance issues, although I did only go max 38km/h (~22mph) downhill and ~36km/h on flat, so I didn’t push past 40km/h yet, but plan on doing so later this day.
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Where you located man? If you’re in the US, I’d like to gift you some top quality filament to monkey with. Either my favorite PLA+ (which should give you better performance without any increased print difficulty), or some PLA-CF, PETG-CF, ABS-CF whatever you feel like monkeying with, just to encourage you to continue playing and reward you for sharing.
Shoot me a PM if you’re game.
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can confirm PLA+ is pretty badass just add fiberglass
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bam
The specs for Kegel cores… we need em linked here.
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@SimosMCmuffin what’s the verdict on these 10x2.5 tires. You still like them? Wheels holding up?
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What size is the rim for the ten inch tyres pls?
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How did they hold up?
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@SimosMCmuffin can you change the title a little?
I made that other thread to cover possibly non pneumatic wheels with printed parts.
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