[FTC]: Split Clamp vs Axle Hub

[aklego]

We use the split clamp in situations where we want to be able to adjust the angular orientation of one component relative to others. For example, two years ago, we had a cam operated limit switch that needed very precise tuning. We mounted the cam on a split clamp and then could adjust as needed.

[F Elliott]

Got it. That makes sense.

Which one has greater holding power on the axle? Specifically which one would you use to mount a gear and wheel? I seem to see both types in use for that.

[RRLedford]

Mount gears or sprockets with non-split hubs directly onto wheels.
Keep gear/sprocket as close to wheel as possible.
Run four long screws all the way through the entire stack - wheel, hub, and gear/sprocket.
Use flat or button head 6-32 screws where close spacing is needed , and countersink for heads as needed
Then drive wheels directly, with axles merely free spinning in the sleeve bearings. No torque applied to axles.

Tetrix axles bend easily and driving wheels via torque applied to Tetrix axles is a very unreliable concept.

-Dick Ledford

[RRLedford]

Originally Posted by F Elliott

Got it. That makes sense.

Which one has greater holding power on the axle? Specifically which one would you use to mount a gear and wheel? I seem to see both types in use for that.

For just the motor, the 6mm (motor size) split clamping 2-piece 16-tooth integrated sleeve-hub from
AndyMark → S25-16T 6mm Bore Aluminum Sprocket (am-3185)
LINK→http://www.andymark.com/product-p/am-3185.htm
PIC:

are far superior to the set screw hubs for holding/gripping the axle and higher levels of frequent reversing torque power transfer. Only the one 16T size option currently offered though.

We will never use a set screw hub on a 6mm motor axle again if possible.
Their performance justifies the high $20 price IMO.
We are using them on our robot for FTC Res-Q. The non-round wheels cause a lot of shock loading to the motor hubs and no loosening of hubs has occurred so far as long as hubs were properly tightened.






BEWARE though that the clamp screw must be torqued quite highly is prone to stripping if not lubricated !!
Be certain to lube the screw with a tiny bit of good high pressure grease prior to installing, but just a little so it stays away from the bore. A high pressure moly grease is best.

I am about to purchase another (6) of these hubs because the first six are working so well!

-Dick Ledford