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851 Precision Woodworking Square

Unmatched Precision and Finest Quality Materials. The 8” long 851 Square (also available in metric scale) start the manufacturing process as a solid piece of very expensive, extremely stable, cast aluminum tool plate. The plate is then carefully machined in multiple, high RPM passes on state-of-art CNC equipment.

The result is a single-piece blade and handle square. This manufacturing process insures the 851 Square is accurate to within .001 inch or less along the full length of the tool.

Once the square is perfect, two pieces of precision-machined aluminum to form the cheeks of the handle. These cheeks are fitted to the handle with two stainless steel dowel pins that ensure bulletproof rigidity and perfect alignment when pressed into their precision-machined holes. This kind of strength and accuracy simply cannot be matched by squares made using separate blade and handle parts or punched-out on a stamping press.

Features Galore. The blades on both squares are ¼” thick and the handle is a full ¾”. The inside edge of the of the square’s handle features a shoulder to allow it to lay flat on the work so you can accurately mark either edge of the blade.

The thick base even makes it easy to stand the blade upright to check square on your table saw blade, jointer fence, band saw blade and other machinery setup operations. With the square standing upright, checking casework parts for square is an effortless, hands-free operation.

Woodpeckers even goes as far as to mill a notch at the inside corner of the square so you can “zero-out” your layout line all the way to the edge of your work.  Easy to read measurement scales are laser etched in 1/16th increments on both sides of the blade (1mm scale for metric).

We’re so confident in the accuracy of the Model 851 Square we offer them with a Lifetime Guarantee to stay square to within .001 inch or we’ll repair or replace it upon return and inspection by us.

Units: Metric - 200mm
Original price $159.95 - Original price $159.95
Original price
$159.95 - $159.95
Current price $159.95

Customer Reviews

Based on 1 review
Milton Simitsakos (Laval, CA)
Dead accurate

Nothing new that I can add about a Woodpecker tool. They’re known to be accurate and built solidly. This square lived up to the Woodpecker reputation.

What I would like to add though was the phenomenal customer service I got from KJP. The square that was initially delivered had a little slop in the handle so I emailed KJP to see if that was normal. They responded immediately, told me that the tool was off spec and mailed me a new one. The entire process took a few days. I’m blown away by their dedication to great service and I can’t recommend them enough.