Rotating Ballnut - design ideas

[Jonathan]

If you're using a double row angular contact bearing, then it doesn't need preloaded, as they come preloaded.

Are you sure about that, I was worried about what I posted here:

According to the SKF site the axial internal clearence for a 40mm bore double row angular contact bearing is 11um. So that's like having 11um end float on the screw if I used the design with the single bearing. I'm not sure how bad that amount is - it doesn't sound like much. C2 clearance bearings only have 2um clearance.

Here's the link:

http://www.skf.com/skf/productcatalo...ogue=1&lang=en



On a related topic, do you think 2 ballnuts like I drew in #13 is sensible for a router? It should enable backlash, and endfloat from the above, to be eliminated I think.