Scraping hard end grain with a negative rake scraper is 'in' these days and a commercial tool, like night follows day, has predictably appeared in our catalogs.
What is this all about, anyway? What is negative rake? Which is raked negative, the long or short bevel? Which bevel is positioned up when negative rake scraping? Is the arris on the front of my Viking hook tool that prevents dig-ins a negative rake scraper? I guess you can't have a scraper's edge without two surfaces (bevels) meeting somewhere. Does their included angle determine rake? If I tilt the flat top surface that completes my standard scraper's bevelled edge downward with the handle upward and the edge kept above center inside and below center outside do I have in effect a negative rake scraper? With a lantern type tool holder I can change top rake on my metal lathe without grinding the bit.
I'm probably just changing semantics instead of rakes; positive, negative, neutral, relief, clearance, whatever. I'd sound even more like I know what I'm saying if I could work in "proprioception", "chatoyance" and "chiaroscuro" in an off-handed manner. I don't and I can't. :)
I sure would appreciate it if some of you would waste some information (empirical or scientific) on me and maybe a few others about scraping with negative rake.
Turn to Safety, Arch Fortiter