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) and vibrations (drive shaft/bearings) over time.
That's why I was thinking m5 setscrews. However 200A 12S heli motors typically use two m4 setscrews on a 6mm motor shaft with a helical pinion and that exerts significant axial torque in addition to the radial torque and they seem to hold up just fine and that is in a sustained high vibration enviroment. In helis there is ALWAYS vibration even if the blades are perfectly balanced due to cyclic pitch control and blade flap (the advancing blade flaps up and the retreating blade flaps down due to different aerodynamic lift and this affects both the main and tail rotor).Interesting idea
I wonder though if it will hold up as the wheels take a lot of beating (uneven terrain and crashes
Can you post a pic of your idea ( screw ) I have a idea of what your thinking about just wanna make sure before I post something
I haven't actually done anything yet but here is a really crude MS paint drawing that should get the idea across. The idea is I drill a tap hole completely through the center of one face of the hex and then thread it with a 5mm tap. Then I put a small flat for the setscrew in one place on the drive cup shaft. Best way to do this is like with a motor shaft that needs a flat added you assemble it first and tighten the screw to leave a witness mark on the shaft then take it apart and add the flat where the mark is with the edge of a dremel cutoff wheel ("shave" it with a few passes)
I can definitely see that working instead of a flat you could simply punch mark the spot and drill a cup there also since a lot of the set screws have a slight dome to them
I'd use cup point setscrews. Even if you always use the same wheel hex/steering block/drive cup together changing the bearings could introduce slop again unless there is some lateral adjustment possible hence the flat.
Didn’t think about that makes a lot of sense. Let me know if you move forwards on the mod definitely be interested in seeing how it goes
I'm going to get a set of these to try it with that way I don't have to drill the expensive Corally stock hexes. It won't matter that the pin is in the wrong position because I won't be using it anyway and if I screw it up tapping it they're cheap so no big loss. The trickiest part is getting the tap started straight, I plan to use a 3D printed jig for both drilling the hole and getting the tap in straight with a tabletop drill press I got off amazon for small R/C stuff years ago. EDIT: I don't mean tap with the drill I'll just get the threads started in the tap hole straight by turning it by hand for a bit then switch to a tap handle.
You can get zero lateral slop without shimming. Shimming has problems like having to choose between 0.03mm of slop or overloading the bearing because nobody makes shims smaller than 0.05mm thick. With a setscrew you just push the hex against the bearing with your finger and tighten the two setscrews on either side, no loaded up bearing, zero slop, job done. Also the wheel hex will not wobble slightly on the shaft with setscrews holding it in place.
I get it. I never got that detailed I guess.
I have the mill makes drilling straight a breeze I still have my Snap On tap and die sets also. If it works out well I’ll give it a go too
It doesn't matter because the hubs will be eccentric no matter what if they have any tolerance between the shaft and the hex, setscrew or no setscrew. But we're talking 0.02~0.03mm. Your tires and wheels and the fitment between the wheel hex and the wheel all are way more eccentric than that so the eccentricity is a drop in the overall bucket. But it also allows the hex to rock on the shaft which you can eliminate with a setscrew.
If they were a single m4 setscrew I would agree but these are a pair of M5 setscrews.
So you plan on drilling our the existing holes and tapping threads into them to utilize set screws in place of the pins? Or new holes combined with the existing pins?
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