In this timber frame quick tip, we’re going to take a look at using a large circular saw to make a drop cut, to make a TF Tenon. Now, this is a really fast way to make a tenon. But I will admit, the first time I did it, it was a little uncomfortable. It took me a while to get used to it. So definitely take your time. Start with a small saw and work your way up. I think you’ll find that this is a great way to speed up the process of cutting a tenon. Make sure you wear eye protection and hearing protection, and that you read and understand everything about your saw. Other than that, let’s get rolling.
To get started, the first thing we’re going to do is to score all the lines we’re going to cut with the power saws. What this does is it gives the saw and your eye a nice line to follow. It also gives a crisp, clean edge. So also, when you go back with a chisel, it gives you something to follow. Then, after that we’re going to cut off each end squarely, making two cuts. For this, we’re going to use my Big Foot, which is a skill saw with a 10 and 1/4 inch big foot kit. You can find these at Amazon.com. Of course, two cuts. This saw cuts four inches, and this is a six by. If you had a 16 inch saw, of course you could do this in one cut. But I’ve never made that investment, and never will.
The next thing we’re going to do is transfer the lines of the tenon down the end. This is going to give us a place to make that drop cut. We’re going to do it with a pencil and then follow it up with a razor knife. Of course, scoring that line so we have something nice to follow. For this, I am using the Borneman square, which is a handy tool. You can pick these up from the Timber Framer’s Guild. They’re great.
Here’s the drop cut. Got the saw going and we’re just going to let gravity work, and just cut each cut. As I mentioned in the intro, it took me a while to get used to cutting things this way, so take it slow. If you’re not comfortable with it, don’t do it. But just make two cuts. This cuts the sides of the tenon. After you’ve gotten this done, the next thing to do is to cut off the shoulders. I’m going to switch to my smaller scale saw to make one cut, because it’s the right size. This is my trusty Porter Cable 7 1/4, that I’ve had for a number of years. It just keeps on giving. One again, that score line gives us that nice line to follow. If you can cut the line just right, that’s all you need to do.
What I did was I offset the tenon from the references two inches, and it’s an inch and a half tenon. So the other cut was a little deeper, and I needed to use the Big Foot here for that cut. There we are.
The next thing to do is just to knock off that block. Sometimes you don’t get everything lined up, so I just grab my Japanese handsaw here, and just cleaned up the edges. Sometimes, you can get that just perfect, it just leaves a little edge there that needs to be cleaned up. So I’m just going to pound down here with my chisel, clean that up. Then pare it up, nice and smooth. Gotta get those corners. I just said to myself several times, I just need to get a clamp, but I was videotaping and so I didn’t. But I would highly recommend, you know, if the piece is moving or doing anything weird, go ahead and grab a clamp. Clamp it down. That way it’s nice and secure. It’ll actually make things work a lot better.
The last thing I’m going to do is just pare down the edges of the end of the tenon here. This just makes sure that when you’re raising, or something like that, it slides in easier and it doesn’t hang up on anything. And that’s it.
Well, I hope you enjoy that video. If you’d like to find out more about timber framing, head over to timberframehq.com. Make sure to sign up for our newsletter and get a free set of Timber Frame sawhorse plans. Take care, and thanks for watching.