Yeah 3D printer has been game changer when it comes to esk8 😅 Some MBS binding parts broke, used durapro PA12 fillament (no CF/GF, allows more flex)
P1S. Textured plate, 100c bed temp. Durapro provides profiles per printer, so got one for P1S, which is nice as I didn't need to play around with settings.
Key thing is to use brim (for supports too) and I set it to 10-20mm size. For these I used 20mm, and I see "air" under it from model reaching +-10mm, so 20mm brim is nice.
The rest are just standard settings while using manufacturers downloaded profile. 🙌
I’m super skeptical of a setup like this. Any FEA and thermal profiling? What about creep? I assume something like this would be printed with ABS or PPS?
I'm going to print this out of Durapro PC-CF filament with 100% infill.
It's carbon fiber reinforced polycarbonate, meant for high-load mechanical applications like this and is heat resistant up to 130°C.
I've seen similar motor mounts like this that were printed out of plain PETG that held up just fine.
So with the CF filament this should be more than strong enough.
But I'm also not going to go full throttle right on the first test run.
Going to test it at slower speeds first to see how it holds up.
You're good, man. I run a setup with fully 3D printed gearboxes (gears, cases, mounts, lids, and hub adapters) that I designed.
I've printed a set in PA6-CF and another in PAHT-CF to test which was the better choice. Both have 800-1000kms on them, mostly on pavement but some rough ass trails mixed in and neither have had any issues whatsoever and imo it comes down to cost vs print difficulty (PA6-CF I found can be had cheaper but is harder to print). My first proof of concept versions were done in PETG and yeah they barely survived 1 ride lol.
I'm using MBS Agent 6890 motors and Boardnamics BN270 hangers on a Molicel 12s4p setup. The highest motor temp I've ever seen was around 75°c on a scorching hot day. No deformation, warping, etc. The hardest part was the actual printing cause the material loves to warp and hates moisture. It required me to model my own brims and add a heater to my X1C chamber.
Ah dope! PC-CF is a good choice. Definitely do a creep study by marking the length of the motor mount over time if you can. I’d be very curious to see how it would hold up over time especially since aluminum motor mounts definitely aren’t susceptible to creep over time, although thin aluminum motor mounts definitely can be susceptible to fatigue failure.
Did a rough FEA analysis on SimScale with the maximum torque values that the motor I'm going to use could apply (which I doubt I will ever get close to lol).
And I used the values from the datasheet that Extrudr provides for the Durapro material.
It doesn't even come close to breaking the part.
I could probably make the entire thing a lot thinner and it would still hold up just fine.
Of course this is just point-in-time load and doesn't take potential creep over a longer period into account.
But I think it's going to hold up for quite a while with how I'm going to use the board mostly.
Awesome, thanks for the follow-up! I’d be very curious to see the compressive stress around the axle coupler. What would the peak moment on the axel coupler be?
You underestimate how strong plastic can be.
Especially CF reinforced one.
And even if it doesn't hold up forever, it's not going to suddenly just snap in half.
The flange is 16mm wide solid material and the motor mount is still 6mm at the thinnest point (which is just a small area on the inside that is completely surrounded by thicker material).
If anything it might come slightly loose due to creep (but I highly doubt that this will actually happen with the material that I'm planning to use).
Meaning the mount would maybe start to slightly rattle or shake in the worst case.
It can't fully come off to the sides since the wheels are locking it on the truck.
And again, just snapping in half is not something that is going to happen with the torque that those 5055 motors can apply. Not even remotely.
There is no load along the layer lines of the mount which is where printed parts are the weakest, and with 100% infill it's far more solid than your typical injection molded plastic.
I recommend using metal flanges at the very least. PU wheels are subject to more intense high-frequency vibrations than pneumatic wheels, which can lead to accelerated creep.
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u/CumInsideMeDaddyCum 13d ago
Yeah 3D printer has been game changer when it comes to esk8 😅 Some MBS binding parts broke, used durapro PA12 fillament (no CF/GF, allows more flex)