Originally Posted by
James Pallas
I read all the things about "Don't scrape the bottom of mortises with your chisels", "You need 35* bevels on chisels" and so on. Yet we take a plane iron with a 25* bevel and shove it with both legs into wood, knots, edge grain, and some very hard wood at a 45* angle and expect it to keep performing. I do get the thing about more brittle steels chipping if you pry with them, that goes for screwdrivers with hard tips too. I also understand there may be issues if you use a 2 lb. hammer like Thor in a fight. But just using your chisel with normal hits with a mallet in a straight manner or scrapping a little is going to ruin the edge.
Tell me what I'm missing here.
Jim
I'm late to chime in, but my plane irons, bench chisels, and mortise chisels all have different edge geometry to foster durability in their intended applications. I can pry and scrape with my mortise chisels because the cutting angle is steeper than on my bench chisels. This said, I can't pare with them. I use my bench chisels with a shallower cut angle. I also don't whack them with Thor's hammer. I'd also never consider blowing through knots with a smoothing plane. I'd use another tool with a more durable edge. I have no "one size fits all" expectations with respect to edge prep.
Sharp solves all manner of problems.