Disappointed in ZDP

S

'songsrflipnswt

Joined
May 23, 2008
Messages
87
My Endura ZDP's edge rolls. Once i get the roll out of the edge, it won't get sharp enough to shave hair no matter how many times i sharpen it. I have a Sharpmaker setup w/ Diamonds with stock Browns and White but would the Ultra Fine ceramic rods get the edge to shaving sharp again?
 
ZDP is one of the most impressive steels I've used. Rolling ZDP is, in my experience, impossible.
Is it something else perhaps? My ZDP Caly 3 and my former ZDP santoku have always been ridiculously sharp.
It may be possible though that you're not actually sharpening the ZDP. The stock sharpmaker rods will have problems doing it. If I remember correctly, the hardness of the ZDP actually exceeds the hardness of the ceramic sharpening rods. I think it can be done, it just takes time. And lots of it.
 
It can be done. I sharpen my ZDP Delica on the sharpmaker all the time. Just be patient. ;)
 
Mr. Clean said:
If I remember correctly, the hardness of the ZDP actually exceeds the hardness of the ceramic sharpening rods.
Click to expand...
nah, zdp has a ton of chromium, and the chromium carbides are not harder than the ceramics.

do not buy ultra fine rods to try to get zdp-189 shaving sharp. Realize a couple things-the diamond rods are harder than the ceramic, and you can get a shaving sharp edge at the grit of those rods. If you are moving on to the brown and white rods before the knife is shaving sharp, you are just wasting time by going to a finer grit (less metal removal) with a steel that is very wear resistant. Get the UF rods after you get your knife shaving sharp with your current setup, then you will see improvements in that sharpness.
 
Listen to Hardheart. I bet you are getting a burr. Sometimes it is hard to sharpen ZDP on the Sharpmaker, but I bet if you get the edge thinned out to well under 15 degrees per side you will have a much easier time doing 15 degree microbevels on the Sharpmaker. You should get a loupe and good light, or my personal favorite, a Radioshack 60-100X lighted microscope ($10-$12) to see exactly what the edge looks like. I bet you have a wire edge which initially feels sharp, and may shave on one arm and not the other, then as soon as you use it it goes dull. Like Hardheart said you should be getting an edge that shaves cleanly off of the diamond rods, then use light alternating strokes on the brown then white rods to refine the edge. I would also use only the flats of the rods to help avoid raising a burr, which is very easy to do on the corners of the Sharpmaker rods. Use the magnification to make sure you don't have a burr, and if you do raise your angle a few degrees and a couple light passes should remove it. Also be sure to keep your rods very clean, as when they load up they don't sharpen nearly as well which leads to burring by pressing too hard.

I personally use DMT diamond plates for coarser grits, then either Spyderco ceramic benchstones or Shapton Glasstones. The Shaptons work great on ZDP, as I get less burring on ZDP than I do on the ceramics, but with plenty of practice and by thinning out your primary bevel to well under 15 degrees per side (a hardware store X Coarse stone can be bought cheap to do this) ZDP can be brought to exceptional sharpness on the Sharpmaker. Once you get hair popping sharpness or better on the fine rods without a burr the UF rods would then be of great use to you to get a sharper edge, but at this point I think patience and practice are what is needed to get your knife properly sharp. I think that using magnification to see what is happening at the edge (and a sharpie to see if you are hitting the edge or the shoulders) and practicing constantly are going to be the keys to getting that shaving sharp edge you want.

Mike
 
Start with the corners of the diamond rods and backbevel at 30 degrees (15 stokes per side), then do flats (10 strokes), move to brown (20 strokes, 20 strokes), move to white (20 strokes, 20 strokes).

If that doesn't work, something is messed up. It's either your technique (sharpie the edge and repeat, checking every so often to make sure you're actually hitting the edge), or it's the knife (which I doubt).
 
I've had a wire edge on a ZDP Delica roll. I finally ran it edge down on a ceramic stone (brown 701 Pro-file) about five strokes to get rid of the burr, then started over. I had a hard time learning to keep my pressure light on the diamond hones, as ZDP at Rc65-67 feels like it is just sliding across the hone. If you use enough pressure to feel the abrasion the way you do on softer steel, you will turn up a burr and probably break it off, leaving a flat edge. Keep your pressure very light, trust the abrasives even if you can't feel them working, and don't count your strokes (that just gets depressing). Once you get a clean edge, ZDP is pretty impressive.
 
yablanowitz said:
I've had a wire edge on a ZDP Delica roll. I finally ran it edge down on a ceramic stone (brown 701 Pro-file) about five strokes to get rid of the burr, then started over. I had a hard time learning to keep my pressure light on the diamond hones, as ZDP at Rc65-67 feels like it is just sliding across the hone. If you use enough pressure to feel the abrasion the way you do on softer steel, you will turn up a burr and probably break it off, leaving a flat edge. Keep your pressure very light, trust the abrasives even if you can't feel them working, and don't count your strokes (that just gets depressing). Once you get a clean edge, ZDP is pretty impressive.
Click to expand...

Forgot to mention that. :o

Harder "super" steels (S90V, ZPD-189, M4) seem to respond much better to lighter stokes on the rods. I saw an almost immediate difference between working the stroke to letting the knife do the work. The steel is hard and you'll definitely be able to tell that, but light easy strokes work better then forcefully swiping.
 
Thanks for the input everyone. As far as my little knowledge on edge defects goes, when i ran my thumb nail down the blade to the edge, it caught on metal buildup on the side of the edge and i assumed that my edge was rolled. Maybe its just a burr but i'm not even positive what rolled, wired edge and burr really mean when defined so could someone explain them the best they can.
 
This may get moved to Maintenance, but here goes.

A wire edge is essentially a burr that is aligned. When you grind steel, whether you do it on a ceramic hone or a bench grinder, it will begin to bend away from the abrasive when it gets thin enough. This very thin strip of unsupported metal is a burr. It can be a good thing, since it lets you know you have ground one side down past the other, and it is time to switch sides. The problem with it is it will easily bend back the other way when you switch and start grinding away at the other side. If you use very light pressure, you can align this less-than-paper-thin strip of steel with the blade. It will feel very sharp, it will shave hair without effort, it will slice free-hanging cigarette paper without tearing, and it will fold over when used on anything tougher. This is a condition known as a wire edge. When you try to cut something harder than a hair, it bends over, or "rolls". Now you have a rolled edge. If the steel is not too brittle, it can be straightened back up by using a burnishing tool, which is a process called "steeling". If the burr has been bent back and forth a few times, it will break off, leaving behind a flat, ragged not-quite-edge, just like the end of a wire coat hanger when you bend it back and forth until it breaks.

Even a good edge can be rolled or chipped when it hits something hard enough. There is a never ending debate on which is better, steel that resists chipping by rolling (bending over) or steel that resists rolling until it exceeds its limits and chips. ZDP-189 falls into the latter catagory with a clean edge, but with a wire edge (or burr if you prefer to call it that) it can roll instead of chipping.
 
josh k said:
forgot to mention that. :o

harder "super" steels (s90v, zpd-189, m4) seem to respond much better to lighter stokes on the rods. I saw an almost immediate difference between working the stroke to letting the knife do the work. The steel is hard and you'll definitely be able to tell that, but light easy strokes work better then forcefully swiping.
Click to expand...

what he said!!!
 
'songsrflipnswt said:
My Endura ZDP's edge rolls. Once i get the roll out of the edge, it won't get sharp enough to shave hair no matter how many times i sharpen it. I have a Sharpmaker setup w/ Diamonds with stock Browns and White but would the Ultra Fine ceramic rods get the edge to shaving sharp again?
Click to expand...

You should be disappointed in your sharpening skills, most likely. Because - sharpen ZDP189 on sharpmaker is simple routine task, many performs without any problems. Lern how to sharpen and you will not be disappointed.

Thanks, Vassili.
 
You must log in or register to reply here.
Back
Top