Machinist square Information & Machinist square Links at HealthHaven.com

Two typical engineer's squares

A machinist square or engineer's square is the metalworkers' equivalent of a try square. It consists of a steel blade inserted and either welded or pinned into a heavier body at an angle of 90°. In the accompanying image, there is evidence of pinning at the intersection of the blade and body, where the heads of two pins are visible as dark circles.

[edit] Use

In use the body is aligned against the one edge of the object and the blade is presented to the end or body of the object. If the end is being checked, then a strong light source behind the square will show any mismatch between the blade of the square and the end of the object. The purpose of this action is to either check for squareness or to mark out the body of the workpiece.

[edit] Accuracy

Machinist squares should have a runout of no greater than 0.0002 in/in.^[1]

Squares must be occasionally checked for accuracy. The four disk method is one way to verify overall squareness but cannot detect bent blades.

[edit] References

^ Horner, Ken (2007), Essential Guide to the Steel Square: Facts, Short-Cuts, and Problem-Solving Secrets for Carpenters, Woodworkers & Builders, Fox Chapel Publishing, p. 31, ISBN 9781565233423, http://books.google.com/books?id=_k5SxcKRxqQC&lpg=PA31 .

[0] Horner, Ken (2007), Essential Guide to the Steel Square: Facts, Short-Cuts, and Problem-Solving Secrets for Carpenters, Woodworkers & Builders, Fox Chapel Publishing, p. 31, ISBN 9781565233423, http://books.google.com/books?id=_k5SxcKRxqQC&lpg=PA31 .

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