Need Help!- Z axis ball screw on interact4

[ronmarkum]

Does anyone know how many balls are in the recirculating ball nut on one of the z axis ball screw? The machine is a Series 2 Interact 4 . Also, are there two ball paths or just one?

Thanks
Ron

[ronmarkum]

Bridgeport Series 2 Interact 4, Z Axis ball screw.

The little external recirculating guides are damaged and let the ball get out of the recirculating track. The little ears on the guides that force the balls back into the recirculating path wore away and the bearing balls escaped and got under the nylon seals. There appears to be no damage to the nut or ball screw. I think it is very repairable if I can find a supplier for the recirculating guides and the nylon seals. Any thoughts on where I might purchase these?

The machine was running fine and tripped the OL3 relay on a z axix move. It took quite awhile to track down the overload and finally the locked ball screw. I started looking at electrical first since I could not get the DC bus to enable. After (accidentally I think) resetting the OL3 the electrical started working. Then when trying to restart the machine the Z axis transformer gave a bad buzz. I immediately shut it off and started looking at mechanical and found the stuck ball screw. I tried to free it up on the machine (big mistake). I could net tell that the balls were past the recirculating point. Finally, disassembled it from the machine and after a minor cleaning and about an hour trying to the get the nut off (could not get all the balls out so the nut would slide) the problem appeared. I've repaired ball screws on other industrial equip and they have little ears that extend into the ball path to force the balls into the recirculating loop.
Is this the case with these nuts?

Thanks
Ron

[mactec54]

Hi ronmarkum
Send it to a repair shop you won't be able to get those parts unless you have another old screw you can take them from, is this a 5mm pitch or 8mm pitch, I may know were there is some parts but will have to know more about your screw, Name NSK etc

[ronmarkum]

Thanks for the reply. Here the info for the ball nut.

NSK Japan
W2502E-2P-CIZ
5U4-425

It is a 5mm pitch and 25mm OD screw.

[mactec54]

Hi ronmarkum
All the screws we have are 32mm not much good for what you want, The screw you have is a C1, which are very expensive, I would think if the ball return tubes are warnout the screw most likely will have some ware as well

A C3 to a C5 grade screw will work ok on your machine, It does not need to be a C1 for your Zaxes

Here is one of many repair companys
http://www.internationalballscrewrepair.com/

[PrecisionSpindl]

Hi Ron,
We have a ball screw repair company in USA that can repair your ball screw. If you need a ballpark repair cost, send an email with some dimensional information - screw diameter, lead, thread length, oal, type of end machining, nut style. A photo or two would be helpful.

David

www.precisionspindleinc.com
haviland@precisionspindleinc.com