Making Scales Without Power Tools
I start with a piece of wood 1/8" thick. I then place the blade I want to use on the wood and trace a rough outline of it with a pencil. After that, I simply sketch approximately what I want the finished scale to look like around it. Just the one scale at first. I cut a rough outline around that using my heave duty crappy pocket knife. You can't get very close to the lines, but after several passes really pressing hard and deep you can basically fold the wood to get your piece out. It is an imperfect system, but it is easier than using the hobby saw I bought.
The next step is to place that roughly cut scale onto the remaining wood and trace it, then repeat the cutting and folding process until you have two roughly identical chunks of wood. You will want to use rubber cement to stick these together. I just slap it right on the wood, press the pieces together, and pile some of my textbooks on top to keep them nice and tight together.
When you are sure that it is nice and dried, you will want to start sanding the single scale you created down to precisely the shape you want. You can also choose to round the edges or leave them angular. If you have a file or two, you can take down a lot of wood quickly, but it goes pretty fast using the lower grit papers in my opinion. When you get the whole thing smoothed out, you will want to progress up through the grits until finishing with a nice smooth polish on them at 1500 or 2000 grit. They should feel glossy if you have done it properly.
At this point, while they are still glued together, I drill the holes. Basically I just eyeball it in terms of drilling straight, and it has worked out very well for me so far. I then progress quickly though the sandpaper grits again to remove the scraps from drilling the hole. You are now ready to separate the scales. Slide a nice thin blade between them and simply pull apart. Rubber cement is magical like that. After pulling mine apart, I roll off as much of the rubber cement as possible, then sand up through the numbers on the inside of the scales. When you are done, put them aside because it is time for the wedge.
Basically I start with a scrap of wood for the wedge. Anything roughly 1" x 1" will work just fine. You basically want to sand it down to about 1/16" at the wide end, and maybe 2/3 of that at the narrow end. Just put it on the sandpaper and bear down harder on one side than the other, doing equal numbers of strokes on each side to get an even angle. I then sand the wedge up through the grits too.
Only after making my 1x1 square tapered like a wedge do I put it down with a scale on top to mark the shape the wedge needs and I drill the hole where it is needed. Then I take the wedge to the sandpaper again and sand it down to those lines, up through the grits to make it nice and smooth. I also like to put a few coats of wax on my wedge at this point so that it contrasts nicely with the rest of the scales. Of course that isn't needed, particularly if you are using two different woods.
This is the point where I finish my pieces. If you are using wax, just follow the directions on the bottle. If you decide to try using super glue, this is the website I used to figure out how to do it. I don't like his directions completely, and I use a plastic bag instead of my finger as well as sanding through all my grits of sandpaper instead of just one and steel wool.
After your pieces are finished and dried, it is time to put them all together. I start by doing the wedge pin. Basically I start with a 1" piece of brass rod, put it through the holes and line up the pieces. I then place a washer over one end of the rod and set the end of the entire thing on top of my file handle. A few decent whacks with a light hammer, and I pull the rod through until the peened end catches on the washer.
I flip it over, trim a little off the end, and put a washer on that side. I then make sure the rod is pulled as tight as possible, and cut off whatever is sticking out the end. A few whacks on this side and a few more on the first side and the wedge pin is done.
There are two options on pinning the pivot. You can follow the same formula as the wedge pin but with the blade in the middle instead of the wedge, or you can add an extra washer on either side of the blade for more space and then follow the formula on the wedge pin. I have tried both methods and both work just fine.
The final step: Sit back and admire your work.