There are many ways to cut tenons to make a mortise and tenon joint to make some piece of furniture. By hand or with the different power tools we may have in the workshop. But we don’t always have all the power tools we would like.
So I thought that, since the jigsaw is one of the DIY tools we all woodworking and DIY enthusiastic always have, and that a table jigsaw is a homemade tool quite easy to make, it was worth trying to cut a tenon on the jigsaw table to see how long it can take me to make one. wooden joints and see how it looked.
The first thing I have to do is to decide on the dimensions of the tenon. In this case the length will be equal to the width of the wood strip I am using (because in another project I will make a joint with another strip of the same length, and I want to make a through mortise and tenon joint with the tenon in sight on the other side). And the thickness of the tenon is equal to the diameter of the drill bit that I am going to use to make the mortise to make the through mortise and tenon joint. The diameter of that drill bit will be about one third of the thickness of the wood strip.
Then, with the marking gauge I will mark the dimensions of the tenon I want to cut.
And with a pencil I go over the marking gauge marks to make them more visible when cutting.
To cut the tenon I want to use, as I said, the jigsaw table with its guide with bearings to keep the blade vertical. And first I’m going to cut along the profile lines that go from the head of the strip to the shoulder line of the tenon (the line that marks the length of the tenon). I just have to have a steady hand and follow the lines. I don’t cut right on the profile lines of the tenon, though, but I cut along the lines with the blade on the outside of the profile lines.
First I cut the width of the tenon. And then I turn the wood strip to cut the height of the tenon.
Now, with the help of my jigsaw table crosscut sled (which doesn’t work well at all, but it did work for this job), I can cut the shoulder line and finish removing the wood.
And with a chisel I clean the corners between the base of the tenon and the shoulder, since in the corners there is a small protrusion of wood that will get in the way when making the joint with the mortise.
I still have to adjust the tenon dimensions to make it a little nicer and so it fits to make the mortise and tenon joint.
Then, I will use the chisel to adjust the dimensions until they match those of the mortise.
And then I use the chisel to round the corners to match the rounded corners of the mortise. As we will see in another post, the system I use to make the mortise using a drill bit leaves the corners rounded, so I either round the corners of the tenon or cut the corners of the mortise to leave them at 90 degrees. A little more work to make these wood joints.
The truth is that this technique to cut tenons to make a mortise and tenon joint takes more time than expected, and it is that on the one hand you have to take into account that the jigsaw does not cut well in the direction of the wood grain (perhaps it will improve a little with a cutting blade suitable for this type of cuts), and on the other hand this wood strip is hardwood, so it requires more power to the saw than the pine or spruce wood that I usually use.