One of the jobs that I have always hated is squaring up a stock blank. I have never bought one that didn't need some work. I've used everything from rasps to planes to a belt sander. It always seems like it takes forever. I got to thinking there ought to be a way to use a router to speed things up, so I came up with this fixture. It's simple to make and inexpensive. You can also use it to cut a straight barrel channel and the ramrod groove.
It's just a 2 sided box with a carriage for the router. The box is made of 3/4" plywood, 6 ft long, 10 1/2" wide (inside measurement) and 2 3/4" deep (inside measurement). I used 5/16" threaded rod with corresponding nuts inletted into the plywood as hold down clamps.
The router carriage is made of 1"x1/8" aluminum angle attached to pieces of plywood. You can move the router back and forth as you slide the carriage forward and backward. I added some adjustable stops to it so that I could cut the barrel channel and ramrod groove.
To use it, just lay the blank in it and tighten the clamps just enough to keep the blank from sliding around. Put the router, with a 3/4" straight bit, in the carriage and adjust the depth until it just touches the blank. Slide the router back and forth in the carriage as you slide the carriage forward. When you get the one side done, flip it over and do the other side. You now have 2 sides perfectly flat. You can then clamp the flat side to the side of the fixture to square the top. You can then cut the barrel channel. After the barrel channel is cut, you can flip it over and cut the ramrod channel.
This really speeds up the process and does a heck of a lot better job than I could using hand tools. Below are some more pictures.
Steve