Making a new handle for a mortising chisel

Brian Eve gave me 3 very nice mortising chisels during our chair building extravaganza event last year.
None of the chisels have got a handle, so my idea is to make three similar handles so they look like a set.
Joshua Klein from "The workbench diary" had a post where he described his method of making octagonal handles.
I think that octagonal handles will look fine on mortising chisels, and since the bolster is a bit elongated, the handles will not be equal on all sides, but will feature two slightly larger sides. This should make a handle that will enable me to automatically position the chisel in the correct way without looking at it first. Or at least that is my theory.

For the handles, I have brought with me some hornbeam that I also got from Brian Eve (He is a really nice guy)

At first I cleaned the blades  in a Sulphuric acid solution just like I did yesterday with the plane irons.

I then started drilling a small hole in the centre of the handle blank. Next I sort of wiggled the drill from side to side in the hole to make it conical.

Then I used my smallest chisel to make the hole fit the tapered tang. I checked regularly that I didn't make the hole to deep or wide.
When the tang fitted so the bolster was around 1/4" from the handle when inserted using only hand pressure, I stopped.

I banged the handle into the table a few times with the chisel inserted to seat it most of the way. After that I turned it around and placed the tip on a knot and gave the handle a couple of good whacks with a big hammer. That settled the tang firmly into the handle.

The blank was then cross cut to 13 cm (5.25"). I chose that length because it seemed appropriate for the size of chisel.

Next I drew a pencil line on the blank that I could plane to. I planed using my smoothing blade to get a decent surface. I managed to take one swipe too many, and nicked the blade hitting the bolster.
After that I was a bit more careful when planing the other sides of the handle.

When the handle had four tapered sides, I drew lines on the corners so I could remove the material and make the handle octagonal.
In order not to jeopardize my plane iron any more, I used a chisel for this operation.
Next step was to chamfer the end of the handle.

At last I sanded the handle to break the edges.

I think the blanks are not completely dry, but I doubt that it will matter. It might even be an advantage since it could cause the tang to start rusting a bit inside the handle thus securing it better.

After having played around with the finished chisel for a couple of hours, I am afraid that the handle is a bit too fat. So I think that I have to try to make it a bit more rectangular in the top of the handle. Right now it is almost square (with the corners removed).

The finished mortise chisel.

Blades before starting.

Elongated hole in the handle blank.

Seated by hand to about 1/4" distance.

Planing to the line.

First four sides planed.

Marking out for the octagonal chamfers.