Recent Blogs
Roller Parallel Ruler Mechanism Explained: How It Works, Parts, Diagram and Marine Navigation Uses
How a Roller Parallel Ruler works, the geometry behind its tracking accuracy, and why marine navigators still use it on paper charts today.
Parallel Ruler (form 6) Mechanism Explained: Four-Bar Linkage Diagram, Parts, and Uses
Form 6 Parallel Ruler explained — how the four-bar linkage keeps the straightedge parallel during translation, with worked numbers for drafting and marine chart work.