Evolving a Dovetail Plane
I was in the middle of paring a dovetail for a demonstration joint as part of my review of the Veritas router plane when I said to myself, “it’s time!”.
For several months I had been thinking about building a plane to cut the male part of a sliding dovetail. Pairing with a chisel to a line cut by a saw, and then cleaning up with Stanley #140 skew block plane, is a fairly quick – and satisfying – process, and the dovetail plane was not so much considered to replace the chisel, but to replace the #140, since it lacked the correct shape to clean up the sidewall. As it turned out, this dovetail plane is able to replace the chisel and saw as well.
I titled this article “Evolving a Dovetail Plane” since there is little original in the work I have done. Firstly, I scoured the Internet for articles and examples of the work of others, and then I converted a tired, old skew rabbet (rebate) plane rather than build a plane from scratch. Knowing this might inspire a few others to do as I did.
There was really only one article of note to be found, that of Louis Michaud. His web pages included plans for dovetail plane based on the conversion of a skew rabbet plane.
It was helpful (to say the least) to also discover that Brian Buckner had built his version of this dovetail plane. Brian does such beautiful work.
In the beginning ….
… there was a tired and old skew block plane. Its body was slightly twisted, the mouth was worn and wide, and the blade was pitted and rusted. It didn’t sound promising.
Elements of a dovetail plane
The various components of a dovetail plane consist of:
A bevel down plane with a blade that is skewed at 15° across the body.
The sole of the plane is at the same angle as the dovetail. In this case, it was set for a 1:6 ratio, which is approximately 10°.
Of note, the sole has been angled such that the leading edge of the blade cut to the outside, while the trailing edge cut into the shoulder of the dovetail.
There is a fence to determine the depth of the dovetail, and there is a depth stop to determine the width of the dovetail.
Since most sliding dovetails are used in a similar way to a dado, that is, across the grain, the plane requires a nicker to precut the shoulder of the dovetail.
Evolving the dovetail plane
First step was to square up the body of the plane. There was a twist in the body and, all in all, I planed off about 1/8” from each side. The body is now 1 1/4" wide. The blade width (including the 15 degree skew) is a smidgeon under 1 3/8".
The second step was to mark off and plane the angled sole. This has the visual affect of reducing the blade skew. I used a 1:6 dovetail marking gauge, drew lines around the body, then planed to these with a jack.
Shaping the sole also opened the mouth wider than desired and, as a result, a hardwood veneer was glued on. The mouth was reshaped and closed up to 2mm. This proved to be a good compromise between the ability to take a thick shaving and a clean one.
Next came the fence. This is attached to the side of the body… …
…. and is adjustable.
The first shavings with the plane were not successful. The sidewall of the dovetail was not cut clean and square (see below). At this stage of the plane’s development I had yet to add the nicker. I felt that would sort it out.
The nicker was constructed from a piece of ¼” chisel. The beveled end was rounded and set at the same depth as the blade.
However the nicker did not improve the plane’s ability to cut a square sidewall. My thoughts then turned to the side projection of the blade, that is, whether this was pushing the plane away from the wall.
I carefully reset the blade, ground a little more (there was a poofteenth protruding over the side of the plane near the top of the blade). But this made no difference.
Then I had an inspired thought - I had shaped the bottom of the depth stop at the same slant as the sole of the plane, and this probably was not permitting the plane to sit squarely on the timber and against the shoulder. So I squared it off.... and you know what … it all came together - perfect dovetail!
The final stretch
After a few tweaks to tidy up the edges, here is the final result:
The next episode of this saga will focus on developing a plane to cut the female part of the dovetail joint.
Regards from Perth,