Getting back into my woodworking lately, and one of the things that's been exciting me is the idea of making my own tools. It's sort of rare anymore, but historically most craftspeople made a lot of what they needed. In the case of woodworkers, it's all the more sensible as a large number of the tools that you need to work wood can themselves be made of wood.
So this is what's called a router plane. It's job is to cut or clean the bottoms of grooves (dadoes or rabbets), partial mortises like those for hinges, and smoothing the inside of things like dovetails.
Metal router planes are still made and sold, and vintage models pop up in decent condition on eBay from time to time as well. In either case, they command a fairly high price for something I may use only occasionally, and the truth is I really kind of just wanted to try my hand at this whole tool-making thing.
I looked at a number of user made router planes online to get a sense for the general structure. Many of them have handles, like mouse ears, on either side of the upper portion. I decided I'd make a mid-sized plane, and as such, the body itself should provide enough room to get my thumbs or even my palms into the effort of pushing the plane.
I had a random plank of zebrawood that was pretty much perfect in width, but to get the right thickness, I'd have to laminate two pieces together. So that's what I did. When I was making this, I hadn't yet acquired and tuned up my smoothing plane, so I used sandpaper glued to a known true surface to flatten the parts. It worked reasonably well, but there ended up being a little gap in places. I think it'll be ok.
Once it was laminated up, I decided to do some rough shaping. First I rough cut the slope off the front, and then used my (hand) jigsaw to cut out the center area. I was lucky enough to have recently received my oscillating spindle sander. I used the belt attachment to do the exterior shaping, but the spindle was particularly helpful for the interior of the plane, which would've taken absolutely forever to get smooth and clean without it. I'm doing my best to use hand tools whenever possible, as I hate the noise and fury of machines for the most part, but sometimes pragmatism really demands a concession.
Initially I was going to make my own blades as well, to take total control over the thing, and I actually did one trial blade out of W2 tool steel that worked really quite well. I think I'll probably make some small chisels out of the same stock one of these days. Ultimately I decided that for the sake of usability and having a wider array of blade widths available to me without the effort of sourcing steel bar stock, cutting and shaping it, honing it, heat treating it, etc. etc., I'd make the plane accept the standard pattern blades, which are pretty inexpensive ($14 for the one I have there, I think) and available in a range of both metric and imperial widths.
The only tough part of that choice was that it required me to cut a diamond shaped hole perfectly straight down through the body. I ended up carefully drilling the hole (I don't have a drill press, alas) with a bit a little smaller than then blade shaft, and then even more carefully paring away what was left with a bench chisel, checking for true regularly.
It's not super easy to see, but there's also a recess carved into the base, to allow the cutter to be fully retracted to just above zero. I did that with a knife and chisel as well.
The next step was to install something to hold the cutter in place. I drilled a hole into the back and added a brass threaded insert. I then cut a knurled brass thumb screw to length so that it would press against the shaft of the cutter and hold it at depth while in use. For the moment, the fit of the mortise is so tight that the cutter stays put anyway, but that'll change eventually.
(The allen key sticking out the side is actually used to separate the blade part of the cutter from the shaft, in order to facilitate sharpening it… I just wanted to make sure it'd never be lost when it came time to sharpen the thing.)
To wrap it up, I did some final flattening of the sole, taking some test cuts as I went to ensure that the blade is exactly square to the surface being cut. It's actually still off by around a thousandth of an inch or two on one side, so I need to do that little bit of additional tuning, but that's fairly minimal. After some final sanding, I finished with a beeswax / mineral oil mixture, which is all I had at the time that's appropriate for this kind of thing, and seems to work well enough.
All told I'm really happy with it. It works like it's supposed to, and I really like the way it looks. Zebrawood is seriously hard, and working with it definitely tested my saws, chisels and my arm endurance during the flattening process, but I learned a bit, and got a good functional tool out of it.