Recurve Stropping Technique

SirGeod

SirGeod

BANNED
Joined
Sep 14, 2013
Messages
121
I recently acquired a Knives Plus Stropblock and I'm not sure how to use it to get a mirror edge on my ZT0350. Could anyone give me any tips? I've looked around on BF etc and couldn't find much if anything on stropping recurve blades.

My 0350 has a 30 inclusive secondary bevel and a 40 inclusive micro.
 
If your ZT-0350 is S30V steel, and still has the factory edge, you'll likely need to do some more fine-grit honing with Fine/EF/EEF diamond and/or ceramics, before attempting a mirror-finish. A strop by itself on the factory edge won't get it there, and especially if your strop block only came with the usual black/white/green compounds. S30V doesn't polish easily, due to the very abundant vanadium carbides in the steel. And the scratch/grind pattern of the relatively coarse factory edge would have to be erased before even considering polishing with a strop. When it does get that far, then diamond or CBN (Cubic Boron Nitride) compounds on the strop will likely handle it more easily.


David
 
It's M390 with a near mirror edge that's been used that was put on by a YouTube buddy of mine.
 
SirGeod said:
It's M390 with a near mirror edge that's been used that was put on by a YouTube buddy of mine.
Click to expand...

In that case, it sounds like you're (luckily) off to a good start, if it's already a near-mirror. You may still want to consider diamond stropping compound (such as from Hand American or DMT) for your strop. If your existing compounds don't quite get it done, that's the route I'd pursue next. Still tons of carbides in that steel, so polishing may still be a challenge with ordinary compounds. Using the compound on balsa wood usually works very well for polishing.


David
 
It's not exactly the issue of the compound per se but rather how to actually strop it. I'm just not sure whether I should strop it like a regular knife or use the edges of the strop etc.
 
SirGeod said:
It's not exactly the issue of the compound per se but rather how to actually strop it. I'm just not sure whether I should strop it like a regular knife or use the edges of the strop etc.
Click to expand...

The recurve can be stropped on the edges of the strop block. Just keep pressure as light as possible, to avoid excessively rounding the apex. This is another reason why stropping on balsa (or most wood) works so well. The wood can be sanded & shaped to blend with the profile of your edge, but will still be firm enough to minimize compression of the strop and rounding the apex of your edge. You could also affix some leather or clean paper to a cylinder (PVC pipe, etc.), and use that for stropping as well. This method also works great for honing edges on most steels, using wet/dry sandpaper or polishing films with the cylinder.


David
 
SirGeod said:
So just strop it like I would normally on the edge of the strop?
Click to expand...

In that circumstance, it's how I'd do it. Keep as much of the blade edge on the flat of the strop as possible, but allow the recurve portion to follow or just barely overhang the edge as you make the normal stropping stroke. Keep a close eye on the bevel-to-strop contact in that portion, and avoid exerting too much pressure near the edge of the strop.


David
 
It just seems counterintuitive doing it that way while keeping a relatively consistent angle but whatever. Thanks for the advice.
 
SirGeod said:
It just seems counterintuitive doing it that way while keeping a relatively consistent angle but whatever. Thanks for the advice.
Click to expand...

The idea is to keep the bevel face flush to the strop (in the specific area making contact), and follow the curvature of the blade's edge while doing so. When done as such, it will always be at the correct angle (though the angle will very likely vary in different portions of the edge), regardless of which portion of the edge is being honed/stropped. It's rare when all portions of a knife's edge are ground at precisely the same angle (in spite of manufacturer's claims of sharpening to a set angle), especially on curved edges. Just make sure the bevel is always flush in the portion making contact at any given time, and it'll always be 'right'.


David
 
Wrapping a firm piece of leather around something that comes close to matching the curve of your blade works well, although going smaller is no real problem. The thing that is MOST important is to keep the stroking action at 90° to the strop. You much turn the blade as the curve progresses over the strop. If you keep it straight, you lose the advantage of the curvature, and will not get a consistent bevel. 90° to the strop at the point of contact...

I glued some hard leather around a couple of one-inch wooden dowels, and use those for stropping hawkbills, kris knives, karambits, or anything with a severe curve. As long as I remember to turn the blade so it's always at 90° to the strop at point of contact, I get good results. In fact, you can wrap sandpaper around a dowel or can for sharpening severe recurves too.


Stitchawl
 
I was shown how to strop khukuris using a dowel with leather cemented around it. This method has worked well for me. I would think you could use the edge area of your strop but you could also make a round one for recurved blades
 
You must log in or register to reply here.
Back
Top