Orac Saddle Ballscrew Refurbishment

All info relating to the Denford ORAC CNC lathes

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Orac Saddle Ballscrew Refurbishment

Post by kfm36 » Fri 16 Apr , 2021 11:11 am

I am restoring a 1986 Orac that is in generally good original condition but I noticed that the saddle ballscrew was rough when rotated by hand. Unfortunately it was not the thrust bearing and despite stripping the ballscrew down, cleaning and lubing it, the roughness did not go away.

I have sent it to a repair company and they were surprised that the ball bearings sat very high on the shoulder of the screw. Reballing with the next size down did not seem to improve matters. The ballscrew didn't show any signs of previous maintenance. Although the screw is ground, the ballnuts Denford used appear to be turned but not ground.

Has anyone else any experience of refurbing these or sourcing a replacement? Denford don't have any more information other than what is in the Orac manual (the original HBC company named in the manual are no longer in business).

Appreciate any help


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