looking for a "center-bore" motor

[sidius]

I see.
Well, this thread has become about mechanical engineering after we found no suitable shaftless motor and decided to separate the rotating part and motor. I should move this question to general/mechanical engineering forums.

One thing I should ask here instead though is, what motor should I get? Sync with the GPU refresh rate is essential to not get mess instead of a 3d volume.

 

[CDRIVE]

After looking at your latest drawing I'm a bit confused as to why you need such a large bore. The drawing seems to indicate that you're only passing a light beam through it. Am I misconstruing that?

Chris

 

[sidius]

That's not the light beam in the illustration, its the light beam path.
The light beam is a video projection that increases in size over distance.

 

[CDRIVE]

That's not the light beam in the illustration, its the light beam path.
The light beam is a video projection that increases in size over distance.

Can that be compensated for by using lenses?

Chris

 

[sidius]

No, lenses can't shrink a video beam to a tiny <1cm beam and than back so easy. If it was so simple I don't think previous works would waste so much time and money on expensive custom center bore motors or custom milled gears/parts. I mean if it was just a light beam maybe, but a projection has to remain the same in the end.
Someone into photonics explained the details to me once, but I don't remember it. I think it has to do with light scattering in a real world imperfect lens.

 

[CDRIVE]

It was just a thought, which is why I posted it as a question and not an option. Optics is not my forte.

FYI: The square frame pillow block bearings you posted employ a grease fitting located on the same real estate you're suggesting machining a V groove. You can't see it in the photos but take a look at the mechanical drawing.

Chris

 

[sidius]

Yeah, doesn't seem like a good idea because of play in the Y axis too.

It's a bummer that there arent any wide shaft motors either. We could always swap a shaft with a tube.

 

[CDRIVE]

There are large shaft motors. We had quite a few at the hospital I contracted at. Some as large as 3" but you'll need a crane to move them!

Chris

 

[sidius]

Yeah, so uh,

What motor would you suggest for a belt setup?
The rpm is going to be between 700 and 900, depending on what fps/volume ''resolution'' balance I end up with.
The rotation has to be in sync with the GPU fps (120 fps/s -> 15 or so rotations/s) .
It seems after I described what is gong to be rotating we agree not much torque is needed.