Precision Squares Vernon Rockville CT
West Hartford, CT
Vernon Rockvl, CT
South Windsor, CT
How to Use Our Favorite Setup Tools
by Richard Tendick
Every woodworker falls in love with some favorite tools now and then. I count on my faithful set of precision squares every day, from milling the first rough board to installing the last brass hinge. They’re the solid foundation of every successful project.
When I was a young woodworker, though, my first affair with an attractive square ended in bittersweet disappointment. This tool was a real beauty. It had a rosewood handle inlaid with brass and a blued steel blade.
As I gained experience, however, I realized my parts weren’t truly square. I blamed everything but the tool itself. One day I compared it to a friend’s square. He was a fussy machinist, so his square was true. Mine was way off! My tool was too inaccurate for critical work but too beautiful to throw away.
My pal clued me in to the best features of a good square, how to test it and how to use it—hard-earned know-ledge I’ll now share with you.
A Classic Precision Square
The most reliable and useful precision square in my shop is a Starrett 12-in. combination square ($64, see Sources, below). Many other finicky woodworkers have told me that they, too, treasure one of these tools. I put my initials on my square and keep it safe in its own special drawer compartment.
Many combination squares aren’t very accurate, but this one is made to extremely precise tolerances and is individually checked before it leaves the factory. A good 12-in. square, like this one, should be no more than .002 in. out of square at the end of the blade (for comparison, a piece of paper is about .003 in. thick). Look for a published tolerance this small when you shop for any type of precision square.
This satin finish is much easier on the eyes than a shiny finish. The ruler has four fractional scales: 1/8, 1/16, 1/32 and 1/64 in. To avoid making mistakes and counting unnecessary lines, use the scale with the same fraction you’re measuring.
6-in. precision combination square
A 6-in. precision combination square is very convenient to carry in an apron pocket. This silicon brass and rosewood jewel is made by Bridge City Tools (see Sources, below).
How Square is Your Square?
No matter how fancy a square looks, when it comes to accuracy, I’ve got to see it to believe it. Inexpensive models, like a 12-in. fixed-blade machinist’s square ($32, see Sources, page 38), should always be tested. Here’s a new variation on an old method of testing any square.
Photo 1: Cut a line down the middle of a piece of tape attached to a melamine board. The bottom edge of the board must be absolutely straight. Check the board’s edge against the top of your tablesaw.