View Full Version : Rotary adapter for vacuum chuck

Marlin R Burkholder
04-08-2017, 5:51 PM
Have double sealed bearing and can't secure the vacuum. The leak is from the bearing.

Don Bunce
04-10-2017, 10:33 AM
Could you give us more info? Is your system commercially made or DIY? Bearing number? Type of lathe? Pictures would help.

Bruce Wrenn
04-11-2017, 10:07 PM
The bearing isn't made to hold vacuum. You need a rotating coupling with a hollow shaft going to chuck.

Brice Rogers
04-12-2017, 12:54 PM
Some thoughts:

Many/most vacuum chucks use bearings.

Some people confuse sealed (RS = rubber sealed) with shielded bearings. You would want the RS not shielded.

I've seen some designs with a set of three RS bearings. A single bearing even if "double sealed" may not be good enough.

You will also want to make sure that there is a (caulked) seal between the outer perimeter of the bearing and the holder and between the inner ring of the bearing and the shaft.

Don't expect to get 29.5 " of Hg. It won't happen. You should be able to work fine if you can get into the 23 or 24" point. Some woods are so porous that you may not be able to even get to 15".