Hartville Tool Centering Steel Rule

WOOD magazine rating
Hartville Tool


The 12" Ruler is 1" wide and has 1/8", 1/16", and 1/32" scales, a self-centering millimeter scale, and an end scale for setting router bit cutting depths, saw blade heights, etc.

WOOD magazine review

Centering Steel Rule

Review Summary

If you have a tough time justifying the purchase of a rule devoted solely to finding the center of a board. Hartville has the perfect compromise: A centering rule that’s also an exemplary standard rule. We tried out five centering rules, and this one proved good enough to hold its own in the standard bench rule category. Hartville devotes only one of its four scales to centering, with markings in 10-mm increments.
(It doesn’t matter that it’s metric; you only need symmetrical markings to find a centerpoint.) Just position the rule so matching increments rest on the endpoints, and mark the center at zero. In addition to this feature, the Hartville rule has standard scales in 1⁄8", 1⁄16", and 1⁄32" increments. The etched markings are graduated in length for quick reference. It also has 1⁄32" end scales for machinery setup. The no-glare finish allows you to write on it with a pencil to mark a dimension when you need to make repeated measurements, and then wipe it off when you're done. Because the tempered rule measures .042" thick, you can count on it to remain straight.

Detailed Ratings

out of 5





Ease of Use




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