BALLSCREW BACKLASH

WE HAVE A CENT VI . IT HAVE A .006 BACKLASH , IT THERE A WAY TO TIGHT
IT . OR REPLACE THE BALLS LITTLE BIGGER TO COMPENSATE PLEASE HELP
ANY ADVISE THANK YOU

is this on a mill or lathe? what model?
The Farmer

You need to find out where the 'slop' is. Work your way through every component-to-component connection until you find what's loose.

Start with the motor-to-encoder connection, then go on to the motor shaft-to-sheave, the sheave-to-belt, the belt-to-sheave, the sheave-to-ballscrew, the ballscrew-to-ballnut, the ballnut-to-carrier, the carrier-to-table/saddle/bolster. If you have a direct-mount motor, check the coupling, etc.

You also have to check the thrust bearings. They trap the ballscrew to the fixed part of the machine so that the ballnut can move the axis. The pre-load on the bearings prevents the screw from moving relative to the saddle/base/column.

You should be able to get the backlash down to a few tenths.

I usually find the bearings are the problem but you have to check the rest to be sure.

Good luck with your search.

Quote:

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Originally Posted by ZZZZ

You also have to check the thrust bearings. They trap the ballscrew to the fixed part of the machine so that the ballnut can move the axis. The pre-load on the bearings prevents the screw from moving relative to the saddle/base/column.

You should be able to get the backlash down to a few tenths.

I usually find the bearings are the problem but you have to check the rest to be sure.

Good luck with your search.

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this was exactly the case on my 1990's DM2900 mill. ihad to preload the thrust bearings by turning the ball screw "tang" while holding the pulley that drive it in place, then locking it all together while under tension using a special lock washer