Re: tensioned ballscrew

--- In CAD_CAM_EDM_DRO@y..., "Doug Harrison" <prototype@c...> wrote:

> I have two ideas that need to be challenged. The screws on the X

axis of my router are ten feet long. They are 1" diameter, .25 pitch
from Rockford.

> 2. Now for the end bearing blocks. I want to use a tapered roller

bearing at each end of the screw and tension the screw between them.
Of course it would be best to have two bearings at each end of the
screw, so I propose putting a regular ball bearing about two inches
outboard of each tapered bearing in the bearing block.

Doug,
My Tree mill uses a single anular contact bearing on each end of the
X-axis with the screw stretched in between. The designers didn't seem
to think that the side forces with big servos and belt reduction were
significant enough to require an additional bearing on each end. The
X screw is about 50" long X 1.25" which will be close to your screw
length with the traveling dampers. They sound like a great idea and
will effectively reduce the screw lenght by 50%.

Roger