Sharpening jigs in general

[Jessica de Boer]

There is some evidence that side sharpening leaves a stronger edge than a back-and-forth direction.

Funny you should say that because researchers at the university of Tokyo found a straight back and forth motion creates the strongest edge.

[david charlesworth]

Jim,
In my experience it is unwise to try and tip the jig.
The edge should rest on the stone at all times.
Correction to squareness is made by pressing twice as hard on the "long" side as the short side. Each stroke will make a small correction.
The whole point of the narrow roller is that it can be overridden. It does not dictate to the tool.

David

[James Pallas]

Jim,
In my experience it is unwise to try and tip the jig.
The edge should rest on the stone at all times.
Correction to squareness is made by pressing twice as hard on the "long" side as the short side. Each stroke will make a small correction.
The whole point of the narrow roller is that it can be overridden. It does not dictate to the tool.

David

Cambering plane blades. You can do that with a narrow roller. Your Kell jig is made to keep it straight so is mark II. Now one of those jigs for carving tools on a grinder that's different. You can do what your experience tells you. Even LN instructions say to flatten the back and straighten the edge before sharpening in the jig, first paragraph I believe where it talks of other makers or old blades. You can't have both crooked edge for reference and jig for reference without one or the other being twisted out of plane.
Jim

[david charlesworth]

Jessica,

Do you know where I can read that research please?

I tend to agree.

David

[Mike Brady]

Kell jig= a terrible ergonomic design, beautifully executed. Ill-suited to the width of almost any sharpening stone so sandpaper on a glass is about it, as far as media is concerned.

[Brian Holcombe]

Funny you should say that because researchers at the university of Tokyo found a straight back and forth motion creates the strongest edge.

This is my understanding as well.

[David Silverson]

Funny you should say that because researchers at the university of Tokyo found a straight back and forth motion creates the strongest edge.

Jessica in the photo you posted explaining your sharpening technique it seems you are sideways sharpening. Do you do that only for chisels?

[Jessica de Boer]

I don't know if it's available online anywhere. My father's old colleague told me about.

I haven't experimented with it myself though. I sharpen with the chisel or plane blade diagonally on the stone.

[David Silverson]

So you don’t then as I thought you were suggesting referencing the Tokyo study use a straight back and forth motion.

[Brian Holcombe]

If Jessica's technique is similar to my own, then it's a lot closer to straight back and forth then it is sideways. Sideways makes an elongated burr from my understanding.

[Jessica de Boer]

So you don’t then as I thought you were suggesting referencing the Tokyo study use a straight back and forth motion.

I simple mentioned their finding. Nowhere did I say that's how I sharpen.

@Brian: This is how I sharpen. This also creates a lot of surface area to help keep the tool stable.

[Brian Holcombe]

That's how I do it as well.

[Warren Mickley]

That's how I do it as well.

Likewise for me.

[Prashun Patel]

Derek, do you sharpen all of your bevel up blades at 60 degrees and higher? My bevel ups are all 25 degrees ground. The thicker irons in fact make bevel ups easier for me to sharpen free hand than the bevel downs (and my irons aren’t even hollow ground).

I find on these that a micro bevel happens naturally when freehanding. I am sure this is because I am unconsciously lifting the heel at some point in the stroke, but this hasn’t adversely rounded the tip. I do suspect that not using a jig probably means I am regrinding more frequently.

[Tony Zaffuto]

That's how I do it as well.

Same with me.