Sharpening Very Narrow Chisels

[Harbo]

I did a bit of sharpening yesterday and came across an AI 3mm and a couple of Japanese 3mm and 1.5mm bench chisels.
They actually did not need sharpening as I very rarely use them but I got to wonder what was the best method to go about it?
Honing the bevels would be OK as my Kell II and even my Eclipse would work as they hold from the sides, but the backs (or fronts as some people call them) is more tricky.
There is very little flat for support and it would be easy to generate a convex i.e. round off the side edges?
I suppose great care is the answer but has anybody got any tricks to help?

Please, please lets not get into the usual wet/dry, scary sharp, oilstone etc arguments??

Rod

 

[Jacob]

I did a bit of sharpening yesterday and came across an AI 3mm and a couple of Japanese 3mm and 1.5mm bench chisels.
They actually did not need sharpening as I very rarely use them but I got to wonder what was the best method to go about it?
Honing the bevels would be OK as my Kell II and even my Eclipse would work as they hold from the sides, but the backs (or fronts as some people call them) is more tricky.
There is very little flat for support and it would be easy to generate a convex i.e. round off the side edges?
I suppose great care is the answer but has anybody got any tricks to help?

Please, please lets not get into the usual wet/dry, scary sharp, oilstone etc arguments??

Rod

The work of a few seconds freehand - but with your index finger right on the end to hold the bevel down without it rocking sideways. Easy to overdo - just one or two gentle passes should do it. No pushing, just pull gently towards you.
Ditto when face down - index finger on the bevel.

NB just one bevel 30º or more - any less and the tip gets really fragile at 3mm.

 

[Richard T]

I suppose to guarantee square and flat, a square block could be held on top of the (honing device of your choice) to slide the side of the chisel against whilst honing underneath.
Maybe not crucial every time but it could be useful if a previous user had left one in a less than good condition ...

 

[woodbloke]

Like you Rod, I've had no probs holding narrow chisels ( I had a 3mm AI and currently use a 3mm Jap chisel) in the Kell III, using an appropriate wedge. The flat back (or front?) is just held carefully on my 3M films...thus far, no issues - Rob

 

[bugbear]

There is very little flat for support and it would be easy to generate a convex i.e. round off the side edges?
I suppose great care is the answer but has anybody got any tricks to help?

Well, there's plenty of surface lengthwise, and that's the only safe direction to work in. As you've worked out, trying to work side to side is going to be VERY prone to convexing the back.

Lengthwise strokes are a pain, but in this case, they're the safest way - fortunately small chisels don't take long to work in this way.

I have a 1/8" wide mortise chisel by I. Sorby that is roughly 1/2" deep in blade section, and is quite pitted on its back. I still haven't got round to restoring it, since it strikes me as "tricky".

BugBear

 

[Paul Chapman]

When doing the back (non-bevel surface) of very narrow chisels, I find it best to hold it down firmly with one finger and pull the chisel towards you. If you do it forwards and backwards I think there is more chance of rounding over the edges.

Cheers :wink:

Paul

 

[matthewwh]

I've had the same experience as Paul, individual pull strokes are much easier to control and when you are removing such a tiny amount of material, speed is much less of an issue than accuracy.

 

[bosshogg]

I sharpen my 1/8" Marples paring chisel clamped in the base of my Faithful guide, as the chisel grove is just to darn big to get a good grip, hone on a diamond plate to get the bevel (one bevel is fine) then still in the guide, on my Escher waterstone, very gentle so as not to dig it in, I then remove from the guide and hone the "back/flat" along the length, not angled or at right angle whatever. If a bur still exists I find it easy to locate the bevel flat on the stone by feel alone and can remove it quite quickly. Sometimes it's worth putting a strip of wet & dry on the end of the stone to lift the edge of the blade by a few thou's, this gives a good honed edge without in reality adding a noticeable bevel to the back/flat. Then it's on to the leather strop followed by a hand strop, due to the thinness of the blade I take great care and work gently to avoid digs or cutting my hand, it works for me...bosshogg

 

[Henry Disston]

Rob mentioned 3M films and this is one of the advantages. I stick them to 12" square granite tiles and working lengthwise is easy. I have only one 1/8" chisel, a Buck sash mortise that gave me some pause. I just took a small piece of wood with a square edge and held the chisel tight to the block while I ran it back and forth on the film to flatten the back. The long bevel is pretty easy to hold with just a fingertip on the very end and pulling toward me.