Rob Cosman's Sharpening Rule
Gallery
Full Description
Customer Reviews
KITs
The most innovative technique in plane sharpening over the last 30 years is the "ruler trick" by my good friend, David Charlesworth.
Traditionally, a sharp cutting edge is achieved by honing the back of your plane blade until it is dead flat (this takes a while), then you hone the primary bevel to achieve a razor sharp edge.
David Charlesworth introduced his ruler trick to save significant time while still achieving a razor sharp edge. Instead of flattening the whole blade back, he places a thin ruler on the stone raising up the blade about 1 degree so he just hones the leading edge, not the whole back. David's "ruler trick" works great and I always use it.
You only need one thing - a small thin ruler. We have our 8 inch long, .018 inch thick sharpening rules custom made without ruler etchings to allow plane blades to glide smoothly across the rule when executing the "ruler trick".
This works just fine. It’s a metal strip, not strictly a ruler with graduations. It measures around .015” thick, about .004” less than the six inch ruler I was using before. The metal is softer than a 6” ruler and will bend if not properly handled. A plastic shipping case is provided to avoid accidental bending. The thinner material sticks (suction) to the swarf better than a 6” ruler, an advantage, and also overhangs my Shapton Pro stones by about an inch on at either end. The overhang allows use of a 1/2” rare earth magnet on the underside of each end, which absolutely prevents slipping in use. Magnets secure it fantastically to a metal diamond lapping plate. This is a lot better than a 6” ruler and I’m sure Charlesworth would have preferred these, if they were available in his time.
works great could not find a ruler that thickness anywhere great item
Pésimo post venta. Aún no recibo la compra y he mandado al menos tres e-mail pidiendo ayuda y nunca he recibido respuesta
Small but mighty indeed! It was worth the wait (3 and a half weeks in my case - from NB Canada to Melbourne Australia). I paired this steel rule with an AdjuStar (another small but mighty tool) and RC’s plane wax. Now I’m keen to get 2x Cosman IBC 2 3/4 plane blade and chip breaker for my old Stanleys, I’m desperate to know if you’ll restock again or have you stopped selling them? I would love to get a Wood River 5 1/2 but it’s just too expensive at the moment. Keep up the great work that you do RC and the team!
Yeah, sorry about the title but it actually fits! Good addition to the sharpening kit!
