Neander mortise and tenons

[Mark Rainey]

In this month's FW magazine, Bill Pavlak of Colonial Williamsburg has a very informative article on mortise and tenon for a frame and panel door. I have been mortising by hand for years and sawing tenons also, but Bill has some excellent advice, including using "dummy tenons". A must read for Neanders.

[Jim Koepke]

Mark, is that Fine Woodworking?

You had me at "dummy tenons." They have helped me a lot when cutting M&T joints.

jtk

[Mark Rainey]

Mark, is that Fine Woodworking?

You had me at "dummy tenons." They have helped me a lot when cutting M&T joints.

jtk

Yes Jim. Pavlak has some of the best advice I have seen recently.

[Warren Mickley]

Both Felibien (1676) and Diderot (1755) mention a tool for for testing mortises, both for square and for depth. Their gauge has a shelf all the way around the gauge that lets you test the depth of the mortise also.

[Jim Koepke]

Both Felibien (1676) and Diderot (1755) mention a tool for for testing mortises, both for square and for depth. Their gauge has a shelf all the way around the gauge that lets you test the depth of the mortise also.

Warren, are there images of these gauges available on line?

Various forms swirl through my imagination on how these could work.

Below are a couple of my mortise checkers.

Test Tenon.jpg

This was used on my Articulated Gate project. It helped to make sure the mortise was to depth, visually square and the sizing of 24 mortises.

For a much larger mortise a gauge block was used:

Mortise Gauge Block.jpg

Again it checked depth, fit and square visually.

Mortise Gauge Block in Mortise.jpg

It sounds like Felibien and Diderot might have had an adjustable tool instead of making a testing tenon for different size mortises.

jtk

[Mark Rainey]

Both Felibien (1676) and Diderot (1755) mention a tool for for testing mortises, both for square and for depth. Their gauge has a shelf all the way around the gauge that lets you test the depth of the mortise also.

That is a nice addition to the dummy tenon Warren. I am going to chop 8 mortises for a table I am making. Pavlak also describes a mortising technique where he starts close to the near end with the bevel away from you, chopping straight down, then slightly advancing and angling the chisel to chop a triangular chip. He then goes back and chops the vertical cut deeper, and then removes a larger chip. Repeat until you hit full depth. Then he turns chisel around and with bevel facing you he chops straight down, levering away from you to remove waste. I have not seen this method of creating a triangle to full depth at first.

[Mark Rainey]

Warren, are there images of these gauges available on line?

Various forms swirl through my imagination on how these could work.

Below are a couple of my mortise checkers.

Test Tenon.jpg

This was used on my Articulated Gate project. It helped to make sure the mortise was to depth, visually square and the sizing of 24 mortises.

For a much larger mortise a gauge block was used:

Mortise Gauge Block.jpg

Again it checked depth, fit and square visually.

Mortise Gauge Block in Mortise.jpg

It sounds like Felibien and Diderot might have had an adjustable tool instead of making a testing tenon for different size mortises.

jtk

Jim, I see you have found the dummy tenon useful!

[Jim Koepke]

Jim, I see you have found the dummy tenon useful!

Yes, it is a quick way to keep a mortise honest.

jtk

[Warren Mickley]

Here is a gauge from Felibien:
Quilboquet.jpeg

For mortising, you want a full flat bevel on your chisel. In cutting, the chisel rides on the bevel, so making a low angle bevel and a secondary bevel makes you have to ride on the tiny bevel, which is a lot less stable. Start at the near end, bevel away, and chop straight down. Then advance the chisel, bevel still away, and chop straight down again. Each time you chop straight down the chisel goes deeper because there is a cavity to push the waste into, and the chisel is self jigging because it travels through your last cut somewhat as it goes down on an angle. Ride the bevel.

[Tom M King]

Being uneducated, I just always called it a test tenon.

[Jim Koepke]

Here is a gauge from Felibien:

Thanks Warren.

jtk

[Derek Cohen]

Both Felibien (1676) and Diderot (1755) mention a tool for for testing mortises, both for square and for depth. Their gauge has a shelf all the way around the gauge that lets you test the depth of the mortise also.

Lee Valley/Veritas has produced tools for testing mortices and tenons. I have a pre-production set. But this is from several years ago, and they must have re-evaluated the demand as small. I have mentioned that I think they are great, but then Covid also came along. Hopefully, one day, Rob Lee will again consider making them.

No pictures, for obvious reasons.

Regards from Perth

Derek

[Edward Weber]

I prefer to make a dummy tenon for each size I need. You only have to make them once.

[Kevin Adams]

Here is a gauge from Felibien:
Quilboquet.jpeg

For mortising, you want a full flat bevel on your chisel. In cutting, the chisel rides on the bevel, so making a low angle bevel and a secondary bevel makes you have to ride on the tiny bevel, which is a lot less stable. Start at the near end, bevel away, and chop straight down. Then advance the chisel, bevel still away, and chop straight down again. Each time you chop straight down the chisel goes deeper because there is a cavity to push the waste into, and the chisel is self jigging because it travels through your last cut somewhat as it goes down on an angle. Ride the bevel.

Warren, I’m sure you’ve said this before, but what angle do you put on your mortise chisels?

Thanks.
Kevin

[Warren Mickley]

Warren, I’m sure you’ve said this before, but what angle do you put on your mortise chisels?

Thanks.
Kevin

I bought a set of mortise chisels around forty years ago. At that time I was under the impression that mortise chisels should have a bevel around 35 and I thought that I would gradually raise the angle as I sharpened. After a few years I was barely up to 31 with some and I gave up trying to change the angle. It is hard to freehand higher angles.

I now think that 30 degrees is fine if you use the chisel without too much abuse, like prying when it is really embedded in solid wood. So I have a little motion that releases the chisel before prying.