Devan,

I was thinking perhaps one of the makers who learned from Mr. Moran might chime in. I met Mr. Moran and talked at length about knives but I don't recall if we directly discussed edge geometry.

The Moran edge is shaped like an apple seed in cross section. It does not have a discernible primary or secondary bevel. It comes off the blade flat in a gentle curve and goes right to the absolute edge. This would provide the needed strength to support the edge while allowing good flow through different mediums.

I'm trying to work up a reply to Devan's question. I think it may require a sketch to illustrate what the shape of edge should look like. I thought that I had seen a video of someone rolling an edge on a grinder. Anyone know of a video like this?

I think Jim Crowell has a video somewhere. Let me look and see. Devan, I do mine with a slack belt, some use a rotary platen. I usually take the edge down to my final measurement, about .020 for hunters and .025-.030 for larger knives. Then I sharpen with the belt grinder on slow speed. Then I will convex or roll the edge. Then strop the edge to remove burrs.

Brion

I think I may have posted this in another forum somewhere around here, but here it is again.

I saw Mike Quesenberry roll the edge at a hammer-in in Casa Grande last year. He has a pretty good technique that I've adopted using the 9 inch disk grinder with a rubber pad glued to the disk. I purchased my rubber sheet from Grainger. It comes in 12"x24" sheets in a variety of durometers and thicknesses. I'm using 3/16" thick and 35 durometer. It takes very little tilt and pressure to roll the edge down to sharp.

Here some videos I filmed at Jim Crowell's shop. I had searched high and low for this info but couldn't find it anywhere on video in detail. So here it is.

http://www.youtube.com/watch?v=BHL0HXnHUmc

http://www.youtube.com/watch?v=OBE06MQspNc

http://www.youtube.com/watch?v=EERAkhyj6UM

http://www.youtube.com/watch?v=UC0mDvWc9e4

Thanks for posting the videos Mitchell!! That's the type of videos that I was looking for. Kyle Royer also has a video of edge rolling in a WIP on his web site.

A lot of guys have added a small platen to their grinders, to hold the belt flat for this work. Below is a picture of the platen that I added to my KMG. I drilled and tapped a bolt hole in the bracket of the flat platen attachment to mount this small platen.

I use Trizact belts to roll my edges. I don't like the way that J-flex belts curl over at both edges of the belt. The Trizact belts are stiffer and run flat.

Below is a sketch of the difference between a typical V grind edge and a Moran, or convex edge. If I haven't illustrated this correctly; someone please say so and I'll change the sketch.

Steve

Do you convex on the small platen, or the slack area in between? Also, what grit trizact belt do you use?

Thanks!

Bob

well,I just went ahead and made a small platen. What a difference it made in convexing the edge. A lot smoother without that belt hump in the middle of the belt! It was pretty easy to make, too.

Bob

Good grief….. I'm sorry Robert. I'm not keeping up with responses to posts.

I start convexing on the small platen, then slack belt just above the small platen to blend in the edge radius.

I start with an A300 Trizact, if I need to work a larger convex edge, like on a camp knife. Then go to an A100 Trizact to finish blending. If working on a smaller blade like a hunter, I typically can get all of the convexing done with the A100 belt.

Steve,

Thank you!

Bob