the motor seems to use a toothed belt to drive ballscrew your backlash may be in the betlt drive between the motor and screw rather than the ball screw itself.
First of all i have never had to refill a ball nut. I did once take an old one apart(on a tractor stearing box). being a complete single trac from start to finish why can you not put all the balls in the same hole and slowly turn the screw to get more balls in, or is yours 4 seperate individual tracks not connected to each other?
Correct, this nut is 4 separate circuits. You can actually tell if a bearing is out of place by turning the screw. If a ball is in a track it’s not supposed to be in, it will run into the wrong side of the deflector and jam the nut.
I’m no expert but I’m guessing your ball screw is a SFU1610 with a -4 nut. So 16mm diameter and 10 threads per inch or 2.54mm thread pitch. The ball nut would be a -4 which has 4 races for balls. Should loads of them on eBay or aliexpress
Thanks for the idea Gord. On a 1610 it isn't 10 threads per inch, and when you think about it, it really wouldn't make sense for a screw manufacturer to express a metric screw with any imperial measurements. The 10 means the pitch of the screw is 10 mm. For every turn of the screw, the nut will advance 10mm. That is a much coarser thread than I have. In my case the part number for this screw would be a 1602.5-4. So far the only manufacturer I can find that lists it in their catalog is NSK. That being said, there is no reason I couldn't retrofit this with something else if need be. Thanks for watching!
Back on the Dyna Myte 2800 CentroidCNC acorn retrofit project. How much backlash is too much?
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the motor seems to use a toothed belt to drive ballscrew your backlash may be in the betlt drive between the motor and screw rather than the ball screw itself.
That is an interesting thought. The belt is kevlar banded and super stiff but that is a possibility.
First of all i have never had to refill a ball nut. I did once take an old one apart(on a tractor stearing box). being a complete single trac from start to finish why can you not put all the balls in the same hole and slowly turn the screw to get more balls in, or is yours 4 seperate individual tracks not connected to each other?
Correct, this nut is 4 separate circuits. You can actually tell if a bearing is out of place by turning the screw. If a ball is in a track it’s not supposed to be in, it will run into the wrong side of the deflector and jam the nut.
25.4 is not a metric approximation. It is the exact conversion factor.
I’m no expert but I’m guessing your ball screw is a SFU1610 with a -4 nut. So 16mm diameter and 10 threads per inch or 2.54mm thread pitch. The ball nut would be a -4 which has 4 races for balls. Should loads of them on eBay or aliexpress
Thanks for the idea Gord. On a 1610 it isn't 10 threads per inch, and when you think about it, it really wouldn't make sense for a screw manufacturer to express a metric screw with any imperial measurements. The 10 means the pitch of the screw is 10 mm. For every turn of the screw, the nut will advance 10mm. That is a much coarser thread than I have. In my case the part number for this screw would be a 1602.5-4. So far the only manufacturer I can find that lists it in their catalog is NSK. That being said, there is no reason I couldn't retrofit this with something else if need be. Thanks for watching!
I would replace the bearings with a matched pair of angular contact bearings....
Many people reball the nuts, with just slightly larger balls....Check the backlash after replacing the bearings.
Spoilers marty! you're jumping to the end of the movie. LOL :-)
I never replaced ball into ball nut. I would replace bearing and ball screw
That dial indicator has limited accuracy.
Indeed, but it was repeatable so it got me in the ballpark.