Rotary Table CNCing

[ptjw7uk]

Irving, your option 1 sounds very similar to my escapades only unforseen problem I had was that with the inner bearing fitted the offset wouldnt(couldnt) turn sufficently to engage the drive. I cured it by using a carbide burr in my drill press to make enough clearance for the bearing.

Peter

[irving2008]

How did you do that? I've added a drawing to show how I propose to do it..

[BillTodd]

Irv, why add the thrust bearing inside the housing?

Would it not be easier to add a pair of deep groove ball bearings in your motor mount to take the thrust?

Or maybe reuse the existing offset bearing but line with a 8mm ID, 10mm OD oilite bearing. This won't require boring out of the table body.

A much better idea IMHO

[irving2008]

Irv, why add the thrust bearing inside the housing?

Would it not be easier to add a pair of deep groove ball bearings in your motor mount to take the thrust?

hmmm... thats an idea.. makes the mount more complex, but would be easier to machine... i'll have a think...

[irving2008]

Ok, heres my thoughts.... the left hand diagram shows an approach using two 10x18x5.5 thurst bearings and a miniature 10x15x4 bearing. the top bearing cap screws on to contol endfloat. The right hand version shows the same idea using two 10x26x8 deep groove bearings to give both axial and radial support.

In both cases there is a central piece that acts as a shaft extender that goes over the existing shaft and is locked to it using a grubscrew or two. The only issue with this design is cutting the threads which are 25 x 1.5 (LH diag) or 27 x 1.5 (RH diag) for the end cap. I don't have a way to do that right now and the tap and die is £50!

Comments?