question for Joe Talmadge...

[jefroman]

I have a question about sharpening and grinds.

What will be harder to sharpen, a hollow sabre ground Delica or a new flat sabre ground Delica? What will happen to the edge of a flat sabre ground knife after a lot of sharpening?? Will the edge become thicker after a lot of sharpening?? If that does happen, is there anyway to thin the edge back down??

Thanks, and sorry for all the questions!

Jeff

 

[Joe Talmadge]

Jeff, provided Spyderco leaves the final edge thickness and angle the same between their flat grind and hollow grind, there shouldn't be much difference at first. I haven't checked head-to-head, but thinking back, I don't think the flat grind is much slower going than the hollow grind -- again, at first. Maybe they've left it a tad thicker at the edge now, but I only have one sample and I'm working by memory rather than measurement.

As you sharpen up, the flat grind will definitely get thicker faster than the hollow grind, and be progressively harder to sharpen. What you can do to lessen the effect is to always grind in plenty of relief before you do your regular grind. So, if you usually grind a 20 degree angle, spend some time grinding in a 15-degree backbevel first -- this will insure that the metal above the final 20-degree bevel isn't too thick. The basic idea is that on the flat grind, keep grinding away some metal before your put your regular edge on it, to keep things thin. You can use an x-coarse hone so it will go faster. Note, though that if you leave the backbevel x-coarse, it will rust faster.

Joe

 

[jefroman]

Thanks again!

Jeff

 

[YoungCutter]

I've said it once and I'll say it again... Joe Talmadge, a man who's forgotten more about sharpening than you or I will ever know.