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Aloha hoggatg,
I don’t recommend such an edge (with secondary bezel) on planer knives. Machines that run at such high rpms will dull a fine edge very quickly. Planer blades for power planers are usually ground to 45 degrees in order to keep a lot more “meat” or thickness of steel at the edge. However, lapping the back side of the blades as described for hand plane blades will give a much cleaner cut. Regarding a slight radius: How to do that is briefly explained in the final part 5 section of the article. The Lie-Nielsen Convex plane is a fine plane usually used for small fine work. The convex is too deep to use for stringers, as it just makes a hollow. Enjoy the ride!
Richard
It’s been a long strange trip, and just checking in…
Richard’s right, as ever. If I might add a little more:
The Lie-Nielsen’s are lovely things…and far beyond my means for day to day hackwork. You kinda want to polish them and put 'em on a shelf rather than actually using 'em.
But you can tune up old planes rather nicely and get them to really perform well. A trawl through The Electronic Neanderthal will get you a lot on that.
Steel power planer blades like those in the Skil or later successors most definitely should be sharpened ‘cobby’ - they deal with impact stresses when they come around and hit the material. You might be able to do that second bevel on a spiral cutter like you find on the Rockwell/Porter Cable but it wouldn’t be easy: they have a bit of blade on the material at all times ( no little planer ripples like you get on Skils ) but y’know, they cut good any way you sharpen 'em.
Sharpening in general: I’m old, old school. As an apprentice, my first ‘skill’ was sharpening things. I still use oilstones at work 'cos here it gets cold and a water impregnated waterstone can freeze and crack. Instead, I’ll tune up a plane iron ( or chisel) with a powered water grindstone ( like http://www.grizzlyindustrial.com/products/Slow-Speed-Grinder/G1036 though mine is an old Delta ) and follow it with a soft Arkansas stone. The water-grinder produces a faintly concave surface which can be brought to perfection with the bench stone.
Other sharpening stuff:
While plate glass is lovely and dead flat, you can fake it with either a nice tablesaw top ( cast iron and milled - wipe off the water that gets away and oil it right ricky-tick ) or some scrap Corian countertop material.
I’m an oil guy, though, except on my really good knives and my straight razors which get the really fine waterstones. . My favorite sharpening oil is now industrial sewing machine oil, a clear mineral oil that’s nice, low viscocity stuff that’s relatively cheap and floats off the metal particles you make working the steel away. Or, cut store-bought mineral oil with lamp oil to get it thin almost like water, lets say milk. Use lots of it and wipe off your stone with a non-fuzzy rag regularly, then re-oil. When you don’t do that, your stone can clog with metal bits. Not good.
Sharpening by hand is a real skill. Practice. If you are getting a convex surface, you’re rocking the plane iron as you work, practice and practice until you just keep that bevel smack on. Having a master boatbuilder for your father helps a lot in that respect, especially if his command of profanity is near-infinite. Sacrificing a little knuckle skin as your gauge helps a lot…run your non-dominant hand low on the blade/iron and against the stone while your dominant hand does the pushing and guiding.
And when you have it all set, well, it makes a particular sound that you want to remember. And that is how you tell when it needs sharpening again, 'cos it stops sounding like that. Amazing, how nice and thin a tissue of wood you can take away when it’s all working right.
Hope that’s of some use
doc…