Kerf Chisel
The kerf chisel is used to deepen the kerf of a half bind dovetail pin in the area where the saw blade cannot reach. This facilitates the easier removal of waste in that area ..

The use of the blue tape is discussed here.
In use …

I
built this tool several years ago after watching a video by Tage
Fride. Tage used a piece of bandsaw blade, which he hammered into the
kerf. This looked rather uncomfortable to hold (!) so I decided to
build a special purpose version.

The
blade is as thin/thick as a standard dovetail saw blade (.020").
I used a beltsander to thickness the steel. It is pretty even in
thickness all the way through - the last thing you want in this
situation is a wedge!
The end of the blade is square. A bevel here would act like a chisel and cleave the wood.


The
origin of this "kerf chisel" was a stainless steel trowel
..
Just
remember that when you use a wedge, even one with parallel sides that
acts like a wedge, there is the danger of splitting wood along the
grain. Always add a clamp across the board (see below). And proceed
slowly. Best to “nibble” along the kerf line than take a big
bite, especially if on the outer edges of the board. Listen and feel
how you are progressing. Having said this, I have had very good
results over the years without splitting boards.

Regards
from Perth
Derek
January 2011 Revised October 2011