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The one factor that determines how long the blade will hold an edge is hardness. I doubt all these blades were of the same alloy - in fact I know they weren't because I have a couple Hock tool steel blades and a Hock A2 blade, along with a Lie-Nielsen A2 blade in the lot. Some blades took longer to get a really sharp edge, but with varying amounts a work all of them could be sharpened to the same degree. The old blades that were really hard - harder than the new Hock blades - were chipped. So I can see why plane makers don't harden to that degree any more. But I think for our purposes a really hard blade (within reason) would be better. We would just have to be careful about slowing down to go over the nodes and not hit our steel planing forms. I did actually chip a blade myself on my planing form - the plane wasn't grooved. But that edge was really nice going through the bamboo. A couple new Stanley blades (made within the last 20 years) almost immediately lost it's really sharp edge in use. The blades made before 1930 or so were thicker and harder. The blades made after 1930 or '32 were hard enough, but a lot thinner. I have the fortune to own a Union bench plane made around 1900 or so. The blade is 1/8 inch thick and harder than blazes. I sharpened a blade marked Stanley that was .072 thick - about 1/16th of an inch. That blade was fairly hard but with about half a dozen chips in the edge. I also own a Fulton and a Sargent bench plane. Both of them have blades that measure .101 thick and from the way they sharpen and how long the edge lasts they are really hard. Haven't chipped them yet, but I grooved those planes. My conclusions: For rodmaking the harder the blade (again within reason) the better. We won't be running into the things that other plane users do that chip the blade edge - knots in the wood, nails, staples, etc. Since we plane a narrow strip under very controlled conditions I think we can use a harder edge without chipping it. New stock blades just don't keep an edge like the older (before 1930) blades. There is a basic difference in the new blades compared to the old blades. I think the difference is the hardness. Older blades are harder but easier to chip. Hock and Lie-Nielsen make very good replacement blades. In fact if I bought a new plane, block or bench, I would immediately get a replacement blade. Except for something like a Veritas plane which says it comes with an A2 blade, but I haven't seen a Veritas blade so I can't say for sure how good it is. (Darryl Hayashida) Old plane blades were made for people who made a living planing and working wood and didn't have time to waste sharpening all the time, new plane blades are made for people who like to make chips and shaving so they have a different alloy and temper. New blades are easier and quicker to sharpen, average guy with a fine India can sharpen one in his garage or shop, and easier to go dull. If you think that old plane blades are wonderful you should try old hand saw blades, twice the saw blades as the new ones and also make great knife and scraper blades. I bought a new hand saw from sears and when it dulled I tried to resharpen it, the hardness was a coating on the teeth and when it wore off what you were left with is soft poor steel. It's the same thing with chisels, the new ones are great for scraping grout from between tile or punching hole in cans of beans but pretty useless for working wood, you have to resharpen about once every hour at best. The best old Stanley plane blades were made from Swedish steel from eskletuna (spelling?) Sweden and stay razor sharp for hours after sharpening on hard white and black Arkansas stones. (Patrick Coffey)
I have two Hock plane blades. They are both approximately the same length and both are quite new. I find that one takes an edge a lot better than the other. Very weird. I sharpen them both the exact same way and for approximately the same number of strokes. (Joe West) One obvious question: did you flatten the entire back of the blade before sharpening the bevel? It makes a HUGE difference. Another issue: do you have a stop block? If you can not get the blade into the sharpening jig consistently, you will be reforming the bevel each time you plane. Wayne Cattanach's book has a picture, as do many other sharpening guides What are you using to sharpen? If you are using waterstones, make sure the stones aren't dished. Rub them together under running water until both are completely flat. Another suggestion. Use a microbevel. If you use the Veritas sharpener, you can hone your primary bevel, then adjust it Up by 2 degrees. Again, it provides a significant improvement in blade sharpness, and really cuts down the time needed to retouch the blade. Didn't I read somewhere that Hock has some kind of special treatment for some of their blades? (Jack Follweiler) Go straight to the source, the Hock web site. You might be thinking of the cryogenic tempering of their A2 Cryo blades. (Darryl Hayashida)
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