We all know, or should know, to not let files and rasps bang against each other or against other metal tools.* They'll get dull, we're told. This is received wisdom; I admit I haven't ever questioned it, let alone tested it. But some of my Auriou and Iwasaki examples are too
2020-04-12
2020-04-05
Some pictures of planes. First a Record #07, late production with plastic handles and screw-type cap (as opposed to a "lever cap")
Next, a Miller's Falls #10 (equivalent to Stanley #4-1/2). Note the articulated lever cap, which seems to focus the pressure on the front edge of the iron more effectively than a plain cap:
