I think i know where this goes.
So instead of the centre shaft we get supplied, this recesses into the centre of the bottom circular base?
I was looking at some trailer assembly parts yesterday and there were sort of similiar bearings there.
I have added 4 roller bearings around the outside of the bottom base, will this negate the need for these?
I am going to be adding a 560mm 1.2mm aluminium sheet to the underside of the base for the current bearings to run on and also for a stepper motor to drive the base on. Driving from the outer edge gives extra reduction, how do you see your bearing incoporated with the following?
http://www.bbastrodesigns.com/cot/rollerdriveaz.jpg
Any idea on a cost, i am going to post a summary sheet of where I believe things are at re motorizing a dob, dob buggies, your bearing, els focusser etc I can then add your cost, micks buggy, etc etc
thanks