You can see how simple the design is in this 3D SketchUp file. It’s made up of four small plywood pieces, a few screws, and two bearings. I’ve designed with my widest plane blades in mind, 58mm.
How to make the sharpening jig:
Let’s take a look at how to build it. First I’ll cut this piece of birch plywood as shown to make the machining process easier. With the router I round these corners in the workpieces and, then I finish machining them with an inverted jig saw.
This is the hole for the screw that will act as pivot point, so we must make sure we drill at the right angle to ensure the rotation is perfect.
Now I can cut lengthwise along both side workpieces. I sand all the surfaces with the sanding disc to achieve a better result, and glue these three pieces together. Looks like the joint is going to need some adjustments.
Now I do some drilling again for the pivot point and to place of the bearings, here I’ll use a bit 0.5mm smaller than the screw. Also I drill the holes will later be used to support the tools we want to sharpen.
Now I’ll try to put the device together. Since the screw I’ll be using here is smaller than the inside of the bearing, I’ll make it thicker with a bit of sandpaper. There are better solutions, but in this case, not a lot of precision is required.
I put them in place and make sure everything works. The front end of the jig should be perfectly parallel to the table, and that seems to be the case here.
Now I’ll cut this aluminum bar I had in my workshop. Maybe it should be a little bit thinner. It must be thick enough to not bend when tightening the screws that hold the tools we’re going to sharpen. I drill and thread the four holes.
Now all that’s left is to try inserting a chisel. Putting it in place and adjusting the angle is quite easy and fast.
Same goes for the plane blades. In this article you will see the sharpening jig in action.