GEC factory edge vs. reprofiling

[Tripton]

Unless you are using the wheels to sharpen in combination with some sort of jig to hold the knife perfectly steady, you are not going to end up with a hollow ground edge.

More likely is they are hand sharpened (as per the pic) on the wheels, and an infinitesimal amount of variation results in a flat/convex edge. Just like all of my knives which are sharpened on my (paper) wheels.

Even if the edge were perfectly hollow, matching with the round of the wheel, it would be such a trivially small amount that a couple passes with a stone would take care of it anyway. The edge is just too small for the hollow grind to have any real effect.

[richstag]

Unless you are using the wheels to sharpen in combination with some sort of jig to hold the knife perfectly steady, you are not going to end up with a hollow ground edge.

More likely is they are hand sharpened (as per the pic) on the wheels, and an infinitesimal amount of variation results in a flat/convex edge. Just like all of my knives which are sharpened on my (paper) wheels.

Even if the edge were perfectly hollow, matching with the round of the wheel, it would be such a trivially small amount that a couple passes with a stone would take care of it anyway. The edge is just too small for the hollow grind to have any real effect.

Hollow is hollow, flat is flat and convex is convex IMO. When you sharpen with a stone wheel it takes off material very quickly and it will leave a hollow edge. If you aren't buying it, take a sharpie to a real hollow edge from a stone wheel and then sharpen it on a flat stone. Let me know where the sharpie comes off.

It will come off at the shoulder and the apex only. I do agree the scale is smaller than on a thick chopper or axe, but it does have real effects on cutting performance and edge durability IMO.

[pertinux]

Cool picture, thanks for that P.

I like the wheel my uncle has at his shop. You sit on a seat and pedal it

I was almost expecting you were going to post a pic of something like that... knowing your sense of humor and all

Ha-- that made me laugh.

One just never knows when I'm going to mix things up, and provide a straight answer.

In this instance, having watched the final step -- sharpening/honing-- while at GEC's rendezvous, I knew what their wheel looked like. I was too in-the-moment while there to take pictures myself, but knew I'd seen those of others that included the wheel in question.

Fortunately the picture above was included in GEC's most recent set of #76 in-progress photographs, so I didn't have to go looking far.

~ P.

[richstag]

Ha-- that made me laugh.

One just never knows when I'm going to mix things up, and provide a straight answer.

In this instance, having watched the final step -- sharpening/honing-- while at GEC's rendezvous, I knew what their wheel looked like. I was too in-the-moment while there to take pictures myself, but knew I'd seen those of others that included the wheel in question.

Fortunately the picture above was included in GEC's most recent set of #76 in-progress photographs, so I didn't have to go looking far.

~ P.

Well thanks again, P

[Tripton]

Hollow is hollow, flat is flat and convex is convex IMO. When you sharpen with a stone wheel it takes off material very quickly and it will leave a hollow edge. If you aren't buying it, take a sharpie to a real hollow edge from a stone wheel and then sharpen it on a flat stone. Let me know where the sharpie comes off.

It will come off at the shoulder and the apex only. I do agree the scale is smaller than on a thick chopper or axe, but it does have real effects on cutting performance and edge durability IMO.

I'll gladly do so, as soon as I find a hollow edge.

Never going to happen.

[richstag]

Tripton,

Pretty ignorant disregarding my experiences with sharpening. I have a lot under my belt, sir...

I'm done with this waste of time.

Kevin

ETA - My apologies for showing little cooth in my response. My patience lacks for folks that have little to share in the way of help and plenty to share in the way of disrespect.

[markpmc]

I re-profile my GEC's to 20 degrees or so. I did have BRKT convex my first #23 when I sent it to the spa. Convex is the way to go on field knives IMO.

[Tripton]

Tripton,

Pretty ignorant disregarding my experiences with sharpening. I have a lot under my belt, sir...

I'm done with this waste of time.

Kevin

ETA - My apologies for showing little cooth in my response. My patience lacks for folks that have little to share in the way of help and plenty to share in the way of disrespect.

I have sharpened a few knives in my day, as well. My original statement still stands, in that an actual hollow edge is nigh impossible to get, due simply to the tiny movements (i.e., angle changes) of the hand while sharpening. Without some kind of stabilization, getting a hollow edge while hand-grinding on a 12 inch wheel is highly unlikely.


Nothing ignorant about it. Seems pretty commonsensical to me.

[yablanowitz]

GECs and Sharpmakers don't play well together in my house. I try to strop to keep the factory edge, but once it needs to be sharpened, I spend days on the sharpmaker to get it back to slicing like I want.

Considering the wider angle on the SharpMaker is 40° included and the factory bevels on my GECs have been 45°+, once you've gone past the point where stropping helps, you're cutting a whole new bevel. That takes a while with the brown rods. They aren't made for hogging off a lot of steel. The diamond sleeves would help a bunch. A DMT Extra Coarse bench stone will do the job in a few minutes.

[J. Oeser]

I understand what you are saying. I have sharpened using wheels and the slightest tip will make that flat. And if the knife is ground thin leaving a very small micro bevel, it will, for all intents and purposes be a flat bevel. However, on some thicker grinds especially on factory knives I can guaranty that I could put a hollow secondary bevel on a it. So in that regard I think Kevin is right on.

I have sharpened a few knives in my day, as well. My original statement still stands, in that an actual hollow edge is nigh impossible to get, due simply to the tiny movemUents (i.e., angle changes) of the hand while sharpening. Without some kind of stabilization, getting a hollow edge while hand-grinding on a 12 inch wheel is highly unlikely.


Nothing ignorant about it. Seems pretty commonsensical to me.

[knarfeng]

I started wondering though, if there is some good reason why the GEC people give the blades such an obtuse angle?

To get back to the original question, IMO, 25° per side, (or perhaps 22.5° per side, half of 45) is a fairly traditional sharpening angle. More acute factory angles are a fairly recent development.

Y'all wanted a completely traditional knife with traditional materials and designs. Ya got one.

That being said, I re-profile mine to 20° per side. I start with a DMT extra-coarse diamond stone and finish on the flat side of a coarse Sharpmaker stone. I cut a lot of hard materials (plastic and the like) and I find that 20° with a somewhat coarser edge works nicely for me. YMMV, of course.

[shrapne1]

Hey guys,
Good discussions are going on in this thread regarding re-profiling. I dont mean to take sides on richstag and tripton's debate, but from years of experience solely using a grinding wheel, i can say that it is absolutely possible to get a clean even hollow grind freehand. This is the only way i do it. The size of the wheel and the thickness of the bevel dictates how "hollow" the edge will be, and it begs to say that sometimes the hollow part can be negligible if you are grinding a low angle (18-20degrees).
Back on topic though. I am so happy to say I received my first GEC yesterday! Im not used to having a knife with no cracks and spacing between the liners and handle, and such beauty! So i know many of you believe in working your knives hard, but this knife is so gorgeous im scared to take off any metal to sharpen it lol.

[black mamba]

To get back to the original question, IMO, 25° per side, (or perhaps 22.5° per side, half of 45) is a fairly traditional sharpening angle. More acute factory angles are a fairly recent development.

Y'all wanted a completely traditional knife with traditional materials and designs. Ya got one.

I have found that traditional steels don't really lend themselves to acute bevels. 420HC, 440A & 440C, Tru-Sharp, all seem to take their best edge for me at around 20° per side. At lower angles I find it hard to remove the burr, and it reforms rather quickly.

1095 and especially Queen's D2 are much better at lower angles. The edges seem to "clean up" better and more easily. But I still rarely approach 15° per side for best results.

[fatcorgi]

Quote Originally Posted by knarfeng View Post
To get back to the original question, IMO, 25° per side, (or perhaps 22.5° per side, half of 45) is a fairly traditional sharpening angle. More acute factory angles are a fairly recent development.

Y'all wanted a completely traditional knife with traditional materials and designs. Ya got one.

I have found that traditional steels don't really lend themselves to acute bevels. 420HC, 440A & 440C, Tru-Sharp, all seem to take their best edge for me at around 20° per side. At lower angles I find it hard to remove the burr, and it reforms rather quickly.

1095 and especially Queen's D2 are much better at lower angles. The edges seem to "clean up" better and more easily. But I still rarely approach 15° per side for best results.

sounds plausible, that traditionals simply had less acute angles, and GECs are inkeeping with that tradition. I heard that axes were always sold blunt, because people using them in earlier times were more accustomed to putting their own edge on them. It would be interesting to know if this was also the case for the knives. Would have to ask our grandfathers about that one.

[black mamba]

I have heard it said, especially of the recent S&M knives, that they were made primarily for the collector market, and so had pretty dull blades to prove that they were factory original, i.e. uncarried and unsharpened. If you found a sharp one, it must have been sharpened by the user, since they all came dull.

[Obsessed with Edges]

I have found that traditional steels don't really lend themselves to acute bevels. 420HC, 440A & 440C, Tru-Sharp, all seem to take their best edge for me at around 20° per side. At lower angles I find it hard to remove the burr, and it reforms rather quickly.

1095 and especially Queen's D2 are much better at lower angles. The edges seem to "clean up" better and more easily. But I still rarely approach 15° per side for best results.

I suppose a lot depends on how a knife is used, as to whether more acute angles are a good fit for the user.

I have a bunch of Case knives in Tru-Sharp (a lot, actually), and a few Bucks as well; all 420HC steel. All of them are ~15°/side or less, and they're great cutters. In fact, that 15° 'threshold' really seems to make a huge difference in edge performance. Buck's 420HC factory edges with the 'Edge 2000' grind are spec'd at around 13-16°/side (26-32° inclusive). This was based on CATRA testing they did that proved the thinner geometry was actually more durable (cut more efficiently, for longer) than their older and thicker edge grinds. When the edge geometry gets thin enough (below a certain point), there's a huge drop-off in the amount of direct pressure needed to initiate and finish a cut, which puts a lot less wear & tear on the cutting edge itself. I noticed this, the first time I really thinned out an edge on a Case stockman's clip blade (in Tru-Sharp). I was initially worried it wouldn't hold up. But the almost effortless slicing is a direct reflection of the cutting geometry's efficiency, and these edges hold up much better than might be expected, for that reason. In particular, during tasks like vegetable cutting on a cutting board, there's much less need to 'chop' into the board, as a slicing or draw cut becomes much easier.

The Case Tru-Sharp blades do form some tenacious burrs & wires, when sharpening. But, once that weakened steel is removed, the remaining edge slices amazingly well and is very easy to maintain on a strop with green or SiC compound, in particular.

All of the knives I've re-bevelled (in any steel) have been done to within the same approximate edge angle limit (15°/side or less), if at all possible. Only possible exceptions are for very small-bladed knives, like a Peanut for example. Otherwise, I've never looked back to anything much wider than 30° inclusive.

[tomsch]

Of the 12 or so GECs I've owned I have reprofiled every single one of them. I use my EdgePro to take them down to about 35 degrees, inclusive, and then put a 40 degree micro bevel. They cut at a completely different level after that.

[bonusmarple]

Most of GEC knives I own goes to the spyderco for a 15 degree bevel. The process takes about 15 minutes per blade, using the diamond through the ultrafine. After that it is a few minutes for touch up every so often. GEC makes a great knife but the factory edge leaves room for improvement.

[tomsch]

Bonusmarple - Are you touching up at 15 degree? How does the edge hold up at that angle? I've been using a 40 degree (20 per side) micro bevel but may go back to 30 inclusive if the edge holds up.

[Bigfattyt]

I have to say, my S&M file and wire came with a pretty decent edge.