One of the first things I wanted to try on the X carve was to cut a mortise and tenon. I actually have had the X carve for a while now and And finally got a chance to give it a try. I knew because I was going to have to cut the end of my material, I would have to cut a hole in my waist board to accommodate the length. because I would be cutting the material on its end, I would also need a way to hold the material in place. So if I was going to make a jig or fixture, I figured I might as well make it so it will also hold the material for the mortise as well.
Rip plywood to size and add rabbit for T-track
I started out by ripping some plywood to 3 inch strips and 1 and a half inch strips, The 3 inch strips will make up the bottom portion and the inch and a half strips will be used for the top. I then decided to cut rabbits on all the strips before I glued them together this saves me from cutting dadoes later, just a little quicker.
Glue each section together
Once all the rabbits were cut I could then glue the 3 inch strips to the inch and a half strips, making sure the rabbits are aligned
Screw the two sections tougher and add support
I then screwed the first section to the second section creating a T-shape. I then used a small piece of scrap material to make a corner brace and screwed it into place making sure the jig is kept square.
Screw T- track to fixture
Then I could screw the T- track into each groove. I did this by drilling holes along the bottom of the T-track and countersinking the holes for the screws
Cut out section of waste board
Now it is time to cut a section out of the waste bored. I use the CNC itself for this task as this allows me to align the fixture with the cut line, ensuring that the jig is in line with the machine. The hole I cut out measures 2″ x 8″
Add block to the bottom of the waste board
I screwed a block to the bottom of the waste board to allow for more support and also another place to clamp to if necessary.
Attach the fixture
I held the fixture in place by using the hold down clamps and making sure it is in line with the hole I cut with the router.
clamp the material to the fixture
Next I could clamp the material into place by using hold down clamps and T bolts in the T track. I was careful to make sure that the material is square to the table in both directions
Draw the mortise and tenon
I drew a simple tenon in sketch up by just drawing a square the same size as my material and then drawing the proper size mortise in the middle
Load tenon into easel
I then loaded the tenon into easel. And then make sure the tenon is cut out on the “outside path” and the outside of the material is cut out “on path” It is also important to make sure the outside portion is cut first. This is down by selecting edit and then going to “bring forward” a few time until its all the way forward.
Load mortise into easel
I then load the mortise into easel. Here you want to make sure the tenon part is set to “fill” and the outside portion has a depth of cut of zero. You also need to turn the whole thing 90 degrees. here you may need to add to the thickness of the tenon by adding some width. I find with loading SVGs from sketch up, when ever you use the “fill” it cuts it about 25 thousands to small. So in easel under the shape tab, I add the 25 thousands. Another important note is to make sure your position is set to 0,0 that way you know to position the centre of the bit right at the corner of the material.
Position the bit
Next we need to position the bit to the very corner of the material. This is because we set the drawing right at 0,0 in easel.
Cut the tenon
Finally we can cut the tenon we want to make sure that the outside is cut first and then the inside cut second. If it cut the inside first, you would only be left with small conners which would just break off if you tried to cut the outside second.
Cut the mortise
Next we position the bit for the mortise by making a mark of the thickness of our material and aligning the center of the bet with that Mark and the edge of the board. We can then go ahead and cut the mortise.
Test the fit
Finally we can tester fit and if it is a slightly snug, fit then you are good to go!!