LM16UU on 5/8" rods?

I recently got a few 5/8" ground aluminum rods. (I also got some Igus bushings but they have quite a bit of play.) 5/8" linear bearings are pretty expensive, but LM16UUs are cheap. 5/8" is 15.88mm, is this close enough to work?

Also: the rods are anodized aluminum, and the bearings use hardened steel balls. Will this cause problems? I plan to build a light-duty CNC router.

EDIT: How about bronze bushings? Do they have tight enough tolerances?

Edited 1 time(s). Last edit at 11/07/2014 01:54PM by epicepee.

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epicepee
I recently got a few 5/8" ground aluminum rods. (I also got some Igus bushings but they have quite a bit of play.) 5/8" linear bearings are pretty expensive, but LM16UUs are cheap. 5/8" is 15.88mm, is this close enough to work?

Also: the rods are anodized aluminum, and the bearings use hardened steel balls. Will this cause problems? I plan to build a light-duty CNC router.

I wouldn't. While the anodized aluminum surface may have a high hardness, it's not a very thick layer and constant back and forth movement I would fear would wear though it and once it's through, things only get worse. The slop also would be significant particularly for a CNC application.

if you are going to use aluminum rods then use nylon bushings anything else will wear down the rods in a mater of a few prints. even better may be to use stainless steel rod

I'm also considering this option. I've seen McMaster carries bearing quality E52100 5/8" rod for a good price with a diameter tolerance of +/- 0.006" (0.15 mm). Would there be too much slop using LM16UU ball bearing?

I'm also considering this option. I've seen McMaster carries bearing quality E52100 5/8" rod for a good price with a diameter tolerance of +/- 0.006" (0.15 mm). Would there be too much slop using LM16UU ball bearing?

I wouldn't use LM16UUs if I were you -- brass bushings might work, though, and they're quite cheap on McMaster as well.

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jamesdanielv
even better may be to use stainless steel rod

Chrome alloy steel rods are usually better options then true stainless unless you're operating in a corrosive environment. The chrome alloy steel have a harder hardness. That being said, it depends also on how the rods are made whether they retain their full hardness or if working them has reduced it from what it was originally spec'ed.

Wiki has some rules of thumb for material choice: [reprap.org] Feel free to edit if you spot something missing.

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