One of the things that is hard to get just right each time is making a straight cut on a piece of wood. And many times you need to make a cut at an angle and it never comes out just right. So I made this sanding jig that will allow me to sand a perfect end on a piece of wood and to do so at any angle as needed.
This board is 14" x 10". It's made up of a particle board base, a sliding sanding block made
from aluminum C-channel, a length of aluminum angle, and a couple of screws. With this tool I can
set the adjustable straight edge to any angle +/- 60°. I then place the piece of wood
against the straight edge with the end of the wood against the sand paper. I can then slide
the sanding block back and forth sanding the end of the wood to the perfect shape.
Here are all the parts. The sanding block is 2" x 1" x 14" aluminum C-channel. The straight edge
is 1/2" x 1/2" x 5.75" aluminum angle. The board is 3/4" x 14" x 10" particle board. The pivot
point is a basic bolt/washer/nut setup. The adjustable end is comprised of a T-nut, bolt, rubber
washer, and brass thumb screw.
This shows the top of the board. I made two precision cuts 1/4" deep in the top of the board
that the C-channel slides in. There is absolutely no side to side play. The micro adjustable
fence on the little table saw yet again comes through. What can't be seen in the picture is what
I did to the right edge of the right groove. To allow the sandpaper to sit below the level of
the board top, but not slide in the entire groove, I cut a 1/16" deep notch less than 1/32"
wide along the main groove. If you look back at the first picture, the bottom of the sand paper
is 1/16" below the top of the board. Without doing this the sanded wood would end up with this
really thin remenant because the bottom of the paper was just that tiny bit too high. This tiny
change to the groove solved that problem.
You can also see the paper gauge reading out all of the angles. I made this up in CAD to get it perfect. It's in 1° increments from -60 to +60. For now it's simply attached with spray adhesive. Let's see how long that lasts.
And finally here is the bottom of the board. This was the fun part to make. I rigged up a simple
jig for a router to cut this out. The router has a 6" diameter base. This groove has a 10.5"
diameter. So I used a small paint can with a 4.5" diameter. I clamped it to the board centered
over the groove center. I then set the router in place with a 1/2" bit. I marked to the two end
points for the groove. I centered the bit over each mark and then clamped a stop board so the
router couldn't go further. With all of that in place I turned on the router, held it against
the first stop and the paint can. I then lowered the bit 1/8" then proceeded to slide the router
along the paint can to the other stop. I turned the router off and repeated this process until
the bit cut through the entire board. I then did this all over again using a 1/2" bit to make
the wide part of the groove. This required moving the stops out a little because the t-nut is
longer than wide. And the depth of the wider groove is only 1/4". The paint can stayed exactly
where it was for the first groove. Other than making a lot of dust, it worked perfectly.