axial dampening on the free end of leadscrew/ballscrew.
I am wondering if anyone has considered adding a spring preload to their ballscrews, to tension the ballscrew. but instead of letting the bearing(s) float, cut a spiral groove in the bore the bearings are located in and fill it with something.. maybe cold patch tar would even be reasonable. polydimethylsiloxane grease would be another.
You would get the benefit of a tensioned screw but would not have the thermal expansion problem associated with a fixed-fixed pre-tensioned ballscrew.
i see someone has already filled a gun drilled ballscrew with some kind of dampening material and is reporting substantial improvements.
given that gun drilled ballscrews may not be all that expensive.. i wonder if a steel rod extending through the screw that doesn't rotate with the screw but is rather fixed to the machine.. with coolant or oil pumped through the gap for cooling.. if the same effect could be realized. dampening would be accomplished by the friction in the fluid between the ballscrew and the rod.
Re: axial dampening on the free end of leadscrew/ballscrew.
Quote:
Originally Posted by
Eldon_Joh
I am wondering if anyone has considered adding a spring preload to their ballscrews, to tension the ballscrew. but instead of letting the bearing(s) float, cut a spiral groove in the bore the bearings are located in and fill it with something.. maybe cold patch tar would even be reasonable. polydimethylsiloxane grease would be another.
You would get the benefit of a tensioned screw but would not have the thermal expansion problem associated with a fixed-fixed pre-tensioned ballscrew.
i see someone has already filled a gun drilled ballscrew with some kind of dampening material and is reporting substantial improvements.
given that gun drilled ballscrews may not be all that expensive.. i wonder if a steel rod extending through the screw that doesn't rotate with the screw but is rather fixed to the machine.. with coolant or oil pumped through the gap for cooling.. if the same effect could be realized. dampening would be accomplished by the friction in the fluid between the ballscrew and the rod.
Do it all the time, drill and thread the end of the Ballscrew I use belleville washers to get the tension I need / want
As for ballscrews with a hole right through is normally used for coolant or a closed loop cooling system, to control thermal expansion they already do this on most high end machines
Buy a Ballscrew with a ball-cage nut is better than filling a screw with something