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I'm working on building a 3D Zoetrope like the Disney Zoetrope in this video. The part that has me stumped is the bearing. I bought a lazy susan bearing but it's a bit loud, doesn't have any mount options, and doesn't spin as freely as I'd like.

I also see turntable bearings that seem like essentially the same thing but with better mounting options. My worry with those is their size. I have a 4 foot platter and most bearings are quite small, which is why I went with the lazy susan bearing at 24" diameter.

Thrust bearings have also come up but the ones I've seen don't have any mount options. They seem constructed exactly as I need them with the bearings being sandwiched vertically (top to bottom), instead of horizontally between an outer and inner ring.

I've also been reading that certain ball bearings have a a radial and/or angular thrust capacity. And that this may provide the rotation I need, though again the mounting options seem really limited for a turning table.

I've been googling for days and seem to have a mental block. I don't know how I would stabilize a 4 foot platter if the bearing is small and centered, like the turntable bearings I found. So, what kind of bearing would be best for this? How would I mount it (if its not super obvious)?

I'm thinking of using a pulley to drive the zoetrope, though I'd prefer a direct connection with the motor drive shaft in the middle of the platter.

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  • $\begingroup$ Did you try lubricating things? $\endgroup$ – Criggie Dec 18 '17 at 19:07
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I would suggest getting an unbraked hub assembly intended for a lightweight trailer. You can get the stub axle, bearings and hub as a set and it gives you a convenient flange mounting for your main platter. As long as the platter itself is reasonably stiff and well balanced it shouldn't need any additional support.

I recently used a similar arrangement for a rotating plinth for a trio of bronze and glass statues with a total rotating mass of around 150 kg with a diameter of 1.0 metres. turntable In this case I just cut the stub axle to the required length and welded it to a 6mm thick steel plate which was bolted into a corresponding plate in the framework of the base, this allowed it to be squared with shims. Note that the castors visible are for moving the whole thing and not related to the rotating mechanism. I was able to stand on the end of one of the rotating arms without any problem.

For the drive you could have a pneumatic or rubber wheel directly driving the underside of the platter. This also gives you to opportunity to fine tune the gear ratio according to where on the radius you put the drive wheel. This is probably the easiest drive solution to implement. You would probably want the motor and drive wheel on a sprung or counter-weighted pivot a bit like the belt drive on a lathe. Here a motor with an integrated gearbox would be make life easier as you won't need to provide a large reduction ratio.

Alternatively you could fix a pulley to the hub itself (note that the axle is fixed and it is the hub which rotates).

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  • $\begingroup$ Interesting! This could definitely work. My other thought was to weld a three way axel and put skateboard wheels on each end. Think like three pipes, connected at the center with 120 degrees between each. And at center, weld on any kind of mount i want to the platter $\endgroup$ – Spidy Jun 19 '16 at 20:51
  • $\begingroup$ That could certainly work too, you could also use fixed castors mounted upside down to do a similar thing, I've seen that approach used for rotating stage sets. $\endgroup$ – Chris Johns Jun 19 '16 at 20:59
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    $\begingroup$ I'd go with pulley drive as in high-end audio turntables. More noise isolation from the drive motor, plus you're far less likely to break something if the platter is stuck or over loaded (the belt will just slip) $\endgroup$ – Carl Witthoft Jun 20 '16 at 12:26
  • $\begingroup$ How about a turntable from a microwave? Generally available from an appliance recycler, and is already equipped with a geared motor. $\endgroup$ – Criggie Dec 18 '17 at 19:08

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