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1. ## Anti-whipping ballscrew idea

Is there any reason why this won't work? On a long ballscrew turning at high rpm's we all know there is a problem with whipping of the screw. A rotating nut system is good but complicated. Why not a piggyback type of arrangement with a Delrin block riding on a linear wagon on the linear profile rail that hits a stop just shy of halfway and therefor stops the screw from whipping as the nut travels to the extreme end of travel. There would be such a setup on each side of the ballnut. In the video I only modeled one support but you get the idea hopefully.

https://youtu.be/kkcVWIsXGjk

2. ## Re: Anti-whipping ballscrew idea

you need two delrin blocks, one on each side of the ball nut. but yes that would work. you could use a magnet in the delrin block to cause it to stick to the ball nut.

i doubt anyone has tried to solve this problem before because the ballscrew whip is as much a problem as is the compression of the ballscrew itself.

meaning when you run into a situation where the ballscrew might whip, you also need it to be thicker so that its axially stiffer.

some of the big machines have gun drilled ball screws (probably machined from dom tubing, but that doesn't matter.) and coolant flows through the ballscrew. the lost mass due to the hole in the middle translates into a higher natural resonant frequency, so that works to solve the problem as well.

3. ## Re: Anti-whipping ballscrew idea

Originally Posted by Eldon_Joh
you need two delrin blocks, one on each side of the ball nut. but yes that would work. you could use a magnet in the delrin block to cause it to stick to the ball nut.

i doubt anyone has tried to solve this problem before because the ballscrew whip is as much a problem as is the compression of the ballscrew itself.

meaning when you run into a situation where the ballscrew might whip, you also need it to be thicker so that its axially stiffer.

some of the big machines have gun drilled ball screws (probably machined from dom tubing, but that doesn't matter.) and coolant flows through the ballscrew. the lost mass due to the hole in the middle translates into a higher natural resonant frequency, so that works to solve the problem as well.
I wrote that two would be needed but I didn't want to model and animate both for time saving reasons.

4. Originally Posted by Black Forest
Is there any reason why this won't work? On a long ballscrew turning at high rpm's we all know there is a problem with whipping of the screw. A rotating nut system is good but complicated. Why not a piggyback type of arrangement with a Delrin block riding on a linear wagon on the linear profile rail that hits a stop just shy of halfway and therefor stops the screw from whipping as the nut travels to the extreme end of travel. There would be such a setup on each side of the ballnut. In the video I only modeled one support but you get the idea hopefully.

https://youtu.be/kkcVWIsXGjk
Does delrin blocks has internal thread or just a journal support?

5. ## Re: Anti-whipping ballscrew idea

Originally Posted by Halbmond
Does delrin blocks has internal thread or just a journal support?