Wear bevel?

[Michael J Evans]

Tonight I could not get a burr on a plane iron I was sharpening, it also would not get sharp even after extensive time on the fine stones.

I normally gauge sharpness by how easy the edge shaves hair. I consider very sharp to be shaving with no resistance.

Anywhoo upon visually inspecting the iron, I noticed a very small band of light right below the cutting edge on the back side of the iron (flat side w/o bevel). It was very very small and much more shiny then what I had polished the back of that iron to.

Is this what's known as the wear bevel, and does it have to be removed to get back to sharp?

Thank you
Michael

[ken hatch]

Tonight I could not get a burr on a plane iron I was sharpening, it also would not get sharp even after extensive time on the fine stones.

I normally gauge sharpness by how easy the edge shaves hair. I consider very sharp to be shaving with no resistance.

Anywhoo upon visually inspecting the iron, I noticed a very small band of light right below the cutting edge on the back side of the iron (flat side w/o bevel). It was very very small and much more shiny then what I had polished the back of that iron to.

Is this what's known as the wear bevel, and does it have to be removed to get back to sharp?

Thank you
Michael

Michael,

Yep, it does

ken

[William Fretwell]

What Ken said.

[Robert Hazelwood]

What you are describing sounds exactly like a wear bevel. The wear bevel prevents you from fully removing the burr when you work the back on a stone. But it should not prevent a burr from forming when you work the bevel side.

If you did not raise a burr then something is going on with the bevel side. Maybe you weren't sharpening at quite the right angle or did not go quite long enough with the coarse/medium stones. The edge could have been dubbed during a previous sharpening and now it requires a lot more work at the normal angle to get back to the edge.

If you have a grinder, it might be a good time to grind the bevel back almost to the edge. That will make it easier to quickly raise a burr.

To remove the wear bevel, work the back (just the portion at the very edge) on a medium-fine stone (I use a soft arkansas, a ~4000-grit waterstone would also work) for 10-20 seconds or until you can no longer see the shiny strip at the edge. Then restore the polish with the fine stone.

[ken hatch]

Michael,

If you want to really get into the sharpening weeds https://brentbeach.ca/Sharpen/bevels.html

[Winston Chang]

I wrote something about wear bevels and burr here: https://sawmillcreek.org/showthread....used&p=3067179

[Robert Hazelwood]

Winston's linked post has some great info and scope pictures of the wear bevel. But I think the wear bevel is not the immediate concern for the OP. He is somehow not managing to sharpen all the way to the tip when working the bevel, so that a burr is never formed in the first place.

[Jim Koepke]

Tonight I could not get a burr on a plane iron I was sharpening, it also would not get sharp even after extensive time on the fine stones.

I normally gauge sharpness by how easy the edge shaves hair. I consider very sharp to be shaving with no resistance.

Anywhoo upon visually inspecting the iron, I noticed a very small band of light right below the cutting edge on the back side of the iron (flat side w/o bevel). It was very very small and much more shiny then what I had polished the back of that iron to.

Is this what's known as the wear bevel, and does it have to be removed to get back to sharp?

Thank you
Michael

If a plane iron has been used for an extensive time without honing it is likely to develop an extended wear bevel.

This will require extensive time on coarse stones before moving to the finer stones.

This is a blessing turned curse on some premium blades. The wear profile is smooth. Most of my older blades tend to wear with small chips in the edge. This reveals the wear in an obvious way. Those that wear without chipping tend to tempt me into going longer between honing. This will produce more of a wear bevel in need of attention.

Some address this with "the ruler trick." This may cause more of a wear bevel to contend with in the future when the blade is honed.

Others find sharpening at the earliest signs of edge wear will make for a smaller wear bevel to contend with when honing the bevel side of a blade.

jtk

[Michael J Evans]

The wear bevel was definitely the issue.
I tried to start with a course crystolon but after a couple minutes gave up.
Decided to bust out the 80 grit PSA and that took care of the grinding portion in short order. Went back up the grits and everything is all good now.

Thanks for all the replies and interesting reads.

Michael

[Jim Matthews]

See David Charlesworth's "ruler trick".

It's an amazing time saver.

[Warren Mickley]

See David Charlesworth's "ruler trick".

It's an amazing time saver.

The ruler trick will work the first time, a one trick pony. Then if you get a large wear bevel again, the ruler trick bevel will have to be lengthened in order to erase the new wear bevel. The ruler trick bevel is so shallow that the change in length (of the trick bevel) is 86 times the depth that is worn away.

[Tom M King]

I never use the ruler trick on anything.

[Robert Hazelwood]

The wear bevel was definitely the issue.
I tried to start with a course crystolon but after a couple minutes gave up.
Decided to bust out the 80 grit PSA and that took care of the grinding portion in short order. Went back up the grits and everything is all good now.

Thanks for all the replies and interesting reads.

Michael

You were grinding the bevel side? One way to remove a wear bevel is to remove a lot of material from the bevel, moving the edge back past the wear. That probably also fixed whatever wear or geometry issue you had on the bevel side.

80 grit PSA is excellent stuff.

[Jim Matthews]

There are those that consider methods not published in the sanctified encyclical of Roubo to be heretical.

The rest of us just want to get on with it, already.
(We even use power tools instead of indentured servants.)

[Charles Guest]

Hone the bevel past the wear, then back off the nice fat burr you worked up as you normally would. Don't wait so long to hone next time. Chisels and plane irons are wasting assets. They are not meant to last three lifetimes. Your goal is to use them up. I'm not suggesting abuse but I'm also not suggesting that using a chisel down to a nub is something to be ashamed of. Quite the opposite.