I'm new to part design/mechanical engineering and I have the following question.

enter image description here

  • Blue: steel shaft, 5/8" diameter, connected to a motor
  • Green: aluminum disk, 10" diameter, 1/2" thick, 3" hole
  • Goal: the shaft should rotate the disk

The Question: I'm wondering how can the shaft be connected to the disk?

I tried searching for bushings, various forms of couplings, etc, but couldn't find anything that can connect the two.

Does this mean I would have to machine my own coupling, and there are no standard fittings/parts that would do the job?

FYI, the project needs high torque, so I'm guessing (please correct me if I'm wrong) that a coupling needs to have a large diameter as to apply the torque at a greater distance from the center.

  • $\begingroup$ Have you searched on here? There was a similar question a while ago... $\endgroup$ – Solar Mike Aug 1 '18 at 21:13
  • $\begingroup$ yes I did search here, and many other places online. Maybe I'm using the wrong search terms or something. $\endgroup$ – Z. Uryum Aug 1 '18 at 21:24
  • $\begingroup$ How high torque? Please note thet the coupling probably does not need to be much larher than shaft. $\endgroup$ – joojaa Aug 1 '18 at 22:34
  • $\begingroup$ It looks like you will have to make your own coupling, even if you were lucky enough to find an off-the-shelf coupling for these dimensions it would probably be VERY heavy and expensive. Machine your own. $\endgroup$ – William Hird Aug 1 '18 at 23:53

Masterdrives.com (.PDF - Catalog: QD Bushings) sells bushings of a suitable size but you may or may not want to do some machining to reduce the "E" dimension. Apparently you want bushing type SF, the E length with that taper is bound to fit. 5/8" bore size is available.

Catalog page:

QD Bushings

Another view of one of those T-bearings:

QD Bushing

Alternatively make your own or have one made for you:

Homemade #1

Another design:

Homemade #2

  • 1
    $\begingroup$ Thank you @Rob for the tip this is very useful! and thanks everyone for your comments. $\endgroup$ – Z. Uryum Aug 2 '18 at 19:06
  • $\begingroup$ One more thing ... QD bushings seem to have two sets of holes (threaded and non-threaded). Do you know why is that? or how is it supposed to be used? Also, is there a way to cap or block the shaft from sliding in/out of the bore? or is the friction grip and keylock enough to keep the shaft secured inside the bushing? Thank you. $\endgroup$ – Z. Uryum Aug 2 '18 at 19:20
  • 1
    $\begingroup$ Machine Screws have threads from head to the end but bolts have a section under the head with no threading. Press-fit will keep it from sliding off or use the more expensive slit-type with the bolt that squeezes it to the shaft. Unless the motor bearings are rated for pushing and pulling it's assumed that the forces will be rotational. $\endgroup$ – Rob Aug 2 '18 at 19:24

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.