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View Full Version : Marking knife for skinny dovetails, and a set screwdriver



derekcohen
14th August 2005, 11:32 PM
Here are a couple of doo-dads I made today. They have been on my To Do list for a while. Nothing particularly innovative or even pretty, just useful.

The first is (what I call) a "chisel marking knife". Well, it is really a chisel-shaped marking knife for skinny dovetails. I decided that I needed a marking knife for very skinny dovetails - to be able to slide a blade between the kerf-wide gap at the top - as I could not use any of the the others that I have because they were just too thick. I have used a Stanley Knife blade to do this to date. I wanted something that could be punched downward on the inside face of the tail or, alternately, could be used as a standard double-sided marking knife. It would just have to be very thin, as thin as a Stanley Knife blade.

This one is made out of a steel plaster trowel (really tough steel - I wonder what it is?). Its final dimensions are 3/4" wide x 1" long and 1mm thick. It is bevelled at the front and sides (45 degree bevels). The plan is to do the saw cuts for the tails - but not cut out the waste - then place the tail piece over the pin piece and mark off the pin placement through the kerfs. Only then cut the tail waste.

The second tool is a small screwdriver for the set screws at the sides of LA planes. The need for this became more apparent with the latest generation of bevel up planes, which have thicker walls and, as a result, the screws are more deeply inset.

This one is just a piece of turned Jarrah handle around a little brass jeweller's screwdriver. More comfortable to use than the tiny thing alone.

Regards from Perth

Derek

NewLou
14th August 2005, 11:51 PM
Gidday Derek!!!

Yer as usual looks handy ....................any chance of a few posts of them in use??............the darkside of my brain tells me they would be great to see them in action!!!!

REgards Lou!!!

derekcohen
16th August 2005, 12:40 AM
Hi Lou

Here is a sequence using the chisel marking knife cutting a really skinny dovetail.

Don't be too critical of the dovetails - they were cut and glued in well under 5 minutes. It took much longer to take the pictures.

The knife works really well (can't say the same for the accuracy of my sawing today!). Just push down and the edge makes a clean, thin line that is easily seen.

The knife can also be used along its side, as a traditional marking knife is used.

As can be seen here, the blade just fits inside the kerf of my LN Independence dovetail saw. It is too thick for a Japanese saw.

The picture sequence is self-explanatory.

Regards from Perth

Derek