From Flat grind to beyond...

[Angelus1781]

If you have a knife that came flat ground, how do you go back changing that? I'm expecting a lot of reprofiling, as want a convex grind. Am I wasting my time or is it possible but a lengthy process?

 

[djolney]

Why would you want to waste so much time, and a well ground/heat treated blade, when you could simply put a convex edge on the flat ground blade in question?

 

[knifetester]

If you have a knife that came flat ground, how do you go back changing that?

Remove the metal you don't want there.

I'm expecting a lot of reprofiling, as want a convex grind.

Use a slack abbrasive, i.e. slack belt or sandpaper on a backing that deforms like closed cell foam or styrofoam.

Doing so you can add convexity to the primary grind quite readily.

Am I wasting my time or is it possible but a lengthy process?

Depends on the tools you are using and your expectaions. If you have a belt sander (cheap at Sears) run it with a slack course belt and you can hog off the metal real fast. Try doing it by hand with fine abbrasive and it will take much longer.

when you could simply put a convex edge on the flat ground blade in question?

That would be my suggestion as well. Full convex grinds are a nice profile for some wood work (mainly soft green woods), as blades ground this way have a much lower tendency to bind than flat or hollow grind blades. See Valiant goloks, or several ABS class makers like Raker (Ray Kirk), Caffery, Wheeler, etc. for an excellent example.

 

[Cliff Stamp]

Why would you want to waste so much time, and a well ground/heat treated blade, when you could simply put a convex edge on the flat ground blade in question?

Many stock removal convex ground blades are actually made by flat grinding a bevel and then convexing it.

-Cliff