Yeah, they had to add one to to me too at some point.
NonFEP film from epax. That typo could not have been worse.
Why not use screws instead of these ‘‘pins’’? weight?
also for the fdm printers screw reinforced parts are nuts
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The kegel pulleys use the pins to keep them centered and aligned but there are holes in between each pin to allow for bolts to go through.
Just did another 20 miles today on my pulleys today. They’re showing no signs of wear so it’s looking good!
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Yeah this is what I do, I haven’t had any of them break, just the teeth wear down and eventually break
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Another 14 miles today. I don’t see any wear at all on the pulleys so all is good!
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For a wheel pulley, resin may last virtually forever, if nothing gets in the pulleys…
For me, plastic pulleys have a downside in that they’re softer, so if any rock gets jammed between the teeth, the teeth are more subject to wear or even worse, the rock can wedge itself in. Aluminum is just hard enough to prevent this.
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I’ve tested with this by doing heavy off roading and while I noticed rocks being flung up and hitting all over the pulleys I didn’t see any issues with chipping. I’ve been slow curing my pulleys to allow them to cure more evenly and this seems to really work a charm.
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Time will tell. A few thousand miles can bring the unexpected.
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Om sorry but I have to agree 50 odd miles is what what many people do in two three days. I would hang back and relax and ride the shit out of them. Get a pulley or two out to friends but selling that’s too early. My opinion anyways.
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I have underestimated 3D printed pulleys in the past, because my life “depended” on it. 3-4 years ago, even though I had access to FDM printer I got my first pulleys printed solid in sls nylon from shapeways. I remember that they were $40 ( not worth it) each. I stopped riding thane and so the pulleys went with them.
Then for my next board I used 3D printed solid ABS and I have done about 1600km on them already and they are still going and it was only about $2 to print. Granted I don’t ride very aggressively, but it shows how strong these things already are.
I think your teeth will be okay for over 1000kms but those kegel pins might break under heavy braking.
1600km ABS. There is definitely some wear on the tooth, but it doesn’t slip yet.
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Those kegel pins are mainly for alignment. There are bolt holes in directly next to each pin.
I guess it depends on your layer height for the print, how many outlines you had, whatnot. My FDM ABS didn’t last for more than 100 miles
I always print things solid with 100% concentric infill. More than needed flow on inside volume…for saving weight and material I incorporate the volume reduction into the parts themselves. With carefully placed fillets etc.
Given your failure at 100miles another thing that comes to mind is that I had liberally applied superglue to the teeth of the abs. My thought then was that it would seep into the tiny spaces in between and provide additional support and a tough coat. Seems like that worked.
Oh yeah I would have to imagine that did wonders. I pronanly could have vapor treated the pullies to get the same effect but I didn’t think of it at the time. I’m on PLA+ ones rn
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Printed pulleys can actually last longer than alu ones. My trampa got printed wheel pulleys (carbon nylon) that still looks new while the motor pulley (aluminum) is worn out from all the gravel
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yeah motor pulleys has to be steel in my opinion, a rigid nylon will probably be your best bet. the amount of rocks, dust and crap is also a contributing factor that I feel like more people should invest time in when designing their drive, same as belt width. im moving to 19mm wide now.
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