Wednesday, January 23, 2013

Converting a skew rabbet plane to a dovetail plane, Pt 1

The job I'm working on right now calls for tapered sliding dovetails. I know there are ways to cut those joints by hand without a dovetail plane, but those methods seem tedious, and I don't have time for that. And I know there are ways to cut them by machine, but those methods don't appeal for one reason or another, mostly because they seem overly fussy, and time consuming.

Truth be told, I could probably have figured out the machine method in the time it's taking me to do this conversion. But I've wanted to add this method to my arsenal since I saw John Reed Fox demonstrate it in a Japanese tool class that I took at the Center for Furniture Craftsmanship, back in 2005. John had his assistant cut the tapered dovetail groove with a router while he was explaining how the plane worked, and when the assistant came back, it took him about a minute to fit the mating board, with the dovetail plane. I was impressed by this, both because it was very cool to watch, and because it was clearly a very efficient way to put a carcase together. But, fast forwarding back to me planning out my current project, Japanese versions of the plane would cost me serious money, and I had this plane on hand. 

Well, that, and fixing up the Spiers plane has given me a real tool-making yen. Yeah... like that's gonna help me focus on my bench work. :-P

Side note, before I proceed. I've gone through phases in my woodworking where I really idealized the purity and (BANG BANG BANG) silence of hand tool woodworking. And I've seen people who know what they're doing demonstrate that it can also be a very efficient way to get things done, if you use the proper methodology and mindset. So my inner purist is laughing his ass off at the fact that I'm using a router table, a table saw, a power planer, a drill press, and a band saw, all to make one measly hand tool.

The photo up top is a 7/8" skew rabbet plane that I bought at an antique shop in Corning, New York, about 6 years ago. I'd intended to get it up to 100% and use it more, and had gone so far as to patch the front right corner, and laminate a rosewood sole onto the thing. As antique wooden planes go, it's not too bad, but had definitely seen some hard times. It was pretty heavily worn, and was shorter in the front than it was in the back. It had a few nail holes in the side, and in the sole. I'm guessing that a former owner used it very regularly, and at one point, scabbed on a fence, or a new sole. There were also nail holes on the side of the plane body, so maybe it was a fence. The factory didn't use quarter-sawn stock, so the growth rings are parallel to the sides, and not the sole, as they should be, so I'm guessing it wasn't a premium model anyway. (Or, maybe the factory had simply stopped caring) Issues aside, there's plenty of length on the iron, and the wedge fits well, so I figured it was worth holding onto.

First things first, I wanted to start with a straight, square, and flat plane body. Like I said, it's not quartersawn stock, so it wasn't as flat as I'd like. I didn't want to take off too much wood if I cold help it, so I flattened one face by hand. I ran the other face through a power planer to get a parallel face, taking very, very fine passes. One side effect of this was to make the iron too wide for the body. This is fine, though, since the iron's going to get reground anyway. I also cut off the rosewood sole, and cut the sole to be parallel to the top. I needed to cut the sole at an angle, since this is going to be a dovetail plane. Bearing in mind that I plan to use the plane in conjunction with a router, I made an angle gauge block with a router bit that had the angle that I wanted, and I used this to set the table saw blade angle. So, I now had a decent blank to start from.

One of the other functional parts of a dovetail plane is a movable fence to gauge how far in the plane will cut. I bounced around a few ideas on how I wanted to set it up, and settled on a fence that looks a little bit like a plow plane fence. To mount this, I needed two posts. I made these on the lathe out of ziricote, because I had some kicking around, and I was feeling fancy. The next step for the plane was to drill holes for the posts, but because the holes in the plane and the fence must match perfectly, I wanted to drill them both at the same time. So, I milled a piece of beech for the fence, and drilled both fence and plane body at the same time. Once that was done, I cut an extension of the escapement through the fence.

The last part of the plane for this step was to laminate a new sole onto the plane. For this, I went again with ziricote. It's related to rosewood, so it's nice and dense. I wiped it down with mineral spirits, and alcohol, and epoxied it to the sole of the plane. Because the sole is beveled, clamping things up can be a challenge, the sole will typically slide to one side. I put some wire brads in the plane body, and clipped them down so that they would bite into the sole, and not let it slide. The sole was milled over-size, and will be planed down when the epoxy has cured.



Read Part 2.
Read Part 3.
Read Part 4. 
Read Part 5. 
The Plane In Use.

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