Thursday, January 24, 2013

Converting a skew rabbet plane to a dovetail plane, part 2

This is where I left off: A plane body, a fence, and two posts. The posts are actually installed backwards in the photo: At one point, I'd considered making a bridle fence, which would have the posts fixed in the plane body, and sticking through the fence. But once I'd cut out the escapement, I realized that wasn't really an option anymore, so they'll be fixed in the fence instead. Some projects are like that.

I turned down the posts to fit on some brass ferrules. The plane body will have thumb screws to hold the setting, and fine adjustments will be made via mallet taps on the posts. Ziricote is hard, but brittle, and splintering can still happen, so I figured the ferrules were a good idea.  Once that was done, I cut a notch in the other end of each post for a wedge, and I epoxied the brass ferrule onto each post.

The fence was the next thing that needed work. The purpose of the fence is to define the length of the dovetail tongue on the end of the board. To be able to do that, it needs to extend underneath the plane. So, I milled another piece to mount onto the bottom of the fence that I had so far, and mounted it with glue and screws.

After that, it was back to work on the plane body. I started by planing the new sole to be flush with the plane body. The next step was to cut a dado for the nicker that I'll need soon. Then I cut through the sole, and shape the bed and the throat, so that the iron could be re-inserted, and would bed properly. I did this mostly by paring carefully with chisels, but final tuning was done with files, for a reasonably tight mouth. At this point, the body was back to 'normal,' and ready for the rest of the conversion.

I decided to add a steel plate to the side of the plane body. Ziricote is pretty durable, but I want to do everything I can up front to prevent wear at the sharp edge of the sole. For a dovetail joint to come together cleanly, that inside corner really needs to be sharply defined. Most of that work will be done by the nicker and the iron, but the edge will be subject to a lot of wear.

Fabricating the plate was a pretty involved process, all things considered. The plate needed to be flattened and gauged. (Made even in thickness) A rabbet had to be cut into the side of the plane body to let in the plate, and holes must be drilled and counter-sunk for mounting. Once the plate's mounted position was established, the bed and throat were laid out on the plate, cut, shaped, faired to the plane body,and a slot cut and filed for the nicker. Note the Emmert is turned around so I can use the metal working jaws... The ability to tilt and turn the vise and work at funny angles was a huge help.

On the list of things yet to do, the dovetail bevel must be filed onto the edge of the plate, and faired to the sole of the plane. Once the sole and the side of the plane have been fully defined, I need to regrind and sharpen the iron, and make the nicker. I also need to drill and install the inserts for the thumb screws that will hold the fence in place. This includes inserting wooden pieces that will press against the posts; I don't want the metal screws to do any damage. At this point, with a working fence, iron, and nicker, the plane should at least be functional. Lastly, I'll clean up and finish the plane.

Read part 1.
Read part 3.
Read part 4. 
Read Part 5. 
The Plane In Use.

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