Brief background... purchased two 3 foot and one 6 foot acme screws from McMaster-Carr. Purchased bearing blocks and 1/2-10 ACME Nut, 5 Start from CNC Router Parts.
When I got those items in along with other goodies, I bench top rigged up some of my parts using one of the 3ft acme screws and was able to slide the bearing blocks along the screw, and without much effort twist on the acme screw.
But when I cut the 6ft screw down to the needed length and then tried to slide the bearing blocks on it, they slide over the screw a little then bind up. You can barely slide then down the bearing by hand until they bind, and then I have to basically hammer then free. The acme screw is VERY snug when trying to twist it onto the shaft, way more effort needed to twist the nut on the screw as compared to the 3ft one.
It is almost like this acme screw is a hair over sized. But I used my caliper tool and checked it out, .4995" everywhere I checked it, same as the 3 foot acme screw that I have no issues with. I tried different bearing blocks on the 6 foot acme screw, no help.
I can see "spots" in random locations along the acme screw, but can't feel anything if I twist it between my fingers.
Right now I'm thinking about scrubbing down this screw with steel wool or something in hopes of cleaning it up and seeing what happens. I'm kind of screwed (no pun intended) because I found this problem after I cut it.
Anyone run into bearings binding when trying to slide the acme screw though them? Any fixes?
Thank you for any help you can offer.