Ian Kirby Woodworking Design: Measuring Tools from Straightedge to Squares
posted on by
Using winding strips While many woodworkers like to eyeball their projects, measuring tools like these winding strips help you get your projects perfect.

As woodworkers, we need to assess four primary types of measurements. They are: alignment (straightness), planar accuracy (twist), angular accuracy (angles) and linear dimension (length). In order to adequately address them all, every woodworker should have at least one of each of the following tools.

Straightedge measuring Use a bevel-edge straightedge to get proper level measurements with a narrower contact face to maximize your field of vision.

A straightedge assesses straightness or flatness. Originally shop-made, it has been replaced by metal versions. The bevel-edge type is preferable to those with thick edges because the narrower the contact face, the easier it is to see inaccuracies in your work.

Winding Strips

Twist is usually called winding by woodworkers. A board or assembly in winding has its ends twisted in opposite directions. To check for twist, you need to sight across a pair of winding strips. They are the basis for measuring planar accuracy — there is no alternative. Winding strips are simply a pair of shop-made, parallel-edged straight pieces of wood of the same dimension.

Squares and Gauges
Measuring with a square Squares are perfect for measuring out angles, 90° for try squares, 45° for miter squares, and sliding bevels for variable angles.

The measuring tools we use to determine angles fall into three sub-groups: try squares, which measure 90°; miter squares, which measure 45°; and sliding bevels, which measure variable angles. A popular alternative to the try square is the combination square borrowed originally from the machinist’s toolbox. Combination squares have several features not associated with try squares. First, the blade is graduated so that it works also as a rule. Second, the blade slides. Finally, the stock measures 45° as well as 90°, or multiple angles if it is the revolving style.

Graduated Scales
Graduate Scale Measurement You can use a graduated scale rules for long, straight-line project measurement, they are usually available in 12" and 24" sizes.

Graduated scales, which include metal tapes, rules and calipers, measure linear dimensions. For most bench work in furniture making, the 12" and 24" rules are both useful sizes to own.

The Vernier caliper, also borrowed from the machinist’s toolbox, is an excellent gauge for measuring the depth of grooves, stopped holes or stopped mortises. The main jaws can be used to measure outside dimensions as well as inside dimensions of grooves or tenons. It’s a highly precise measuring tool.

posted on October 1, 2010 by Ian Kirby
previous post next post
Leave a comment