Need a motor shaft coupler

[karrotx]

I need to couple a semi circular shaft to a square shaft of a different size. I don't have calipers to measure the exact size but if you need that information I will buy a pair.

On the left is the DC motor shaft, on the right is the square shaft I need to connect it to. A few options I was consider is welding the two, which doesn't seem like a great idea, or milling the motor shaft down to the same shape as the square shaft.




Here is the motor and shaft:




What are my options? I need this done as soon as possible.

[rbtying]

If you can mill, just make a female-female coupler: one end which accepts the half-flat motor output, and another that accepts the shaft.  Drill a hole through both shafts and screw through - then it should be mechanically stable.  Set screws may also work, depending on the size.

[Soeren]

Hi,

Depending on the power transferred, perhaps a strong and very tight fitting tube of sorts could be used. Something with a strengthening weave, as the pressure hoses used on cars for oil.

Anyway, it all depends on the application, where it's gonna be used and forces (rotational as well as lengthwise.