Small ruler (~6 inch) with strange markings. Bought a slide rule

Design And Build Your Own Circular Slide Rule

Pocket Slide Rule Collectible Slide Rules for sale

The Rhino Carpenter's folding ruler has a 1/2 x 6' Carpenter's Scale with (Ft/In/16ths) on both sides. It is available in 3 styles: outside reading, inside reading, or outside reading with a sliding extension. The Carpenter's folding ruler is made of polyamide reinforced with 30% fiberglass and designed with 90° positive stop joints and deeply embossed scales that won’t wear away under harsh working conditions.

Rhino Rulers Folding Outside Reading Carpenters Ruler

Pocket Slide Rule Collectible Slide Rules for sale

vicrays Woodworking Ruler Precision Pocket Rule - 12, 8, 6 inch Metal Slide Stop Marking Ruler Metric inch Measuring Wood Working Scribi

What Can You Do With A Slide Rule?

What are these 12 rulers used for? They don't have standard marks except for the inches. The gauge is with 11 or 14 marks per inch or 14 or 18 marks per

National Museum of American History

Six inch PICKETT & ECKEL Slide Rule with Original Leather Sheath - 768 – Jim Bode Tools

Metric Vs Imperial - The English Woodworker