Welcome to my shop. This time we’re going to be talking about my bandsaw dovetail cutting jig. I’ve been using this as long as I’ve been making videos, and I have gotten questions about this thing so many times over the years. Finally, eight years later, we are going to cover this topic.
Here you can see the jig in action. It allows you to use your fence in conjunction with this jig to cut the angles for your tails, so, this is a great way to quickly and accurately cut all your tails. Because you can flip the piece as you’re working, you can make your tails symmetrical as well. This jig looks very simple, and for the most part it is, but there are some details and minutiae that I want to talk about.
Let’s talk about dovetail angles first. If you’re looking at this from a hand tool perspective, you’ll typically see those expressed as a rise of a run ratio. If you’re looking at more of the power tool side, those are typically going to be expressed more into straight degrees. For this, we’re going to focus on rise of a run since that is a little more common, especially, if you’re looking at doing this as a way to compliment your hand cut dovetail strategy.
There are a couple of common ratios and a couple of common thought processes. Two common ratios are a 1:8 and a 1:6. A 1:8 is a shallower angle and it is better for hardwoods, while a 1:6 is a steeper angle and better for soft woods. In reality, do whatever you want. It makes absolutely no difference.
So what do those ratios mean and how do we turn those into angles that we can cut? For example, a 1:8 ratio means that for every eight inches of run, you have one inch of rise. So if I connect this point to the front edge of my workbench, this is angled at a 1:8 ration. (Here’s a bonus combination square tip for you. Know the width of your blades, because that can come in pretty handy. On the 12 inch combination square, the width of the blade is one inch, so that means the halfway point is a half inch. You can lay things up pretty quickly, if you just happen to know that this is an inch wide.)
One of the nice things about expressing your angles as a ratio like this is that you don’t need a protractor to draw that line. As you can see, I didn’t draw or set a protractor to 7.13 degrees. I just made a couple of lines, connected to the dots, and that is my angle. With that being said, it is totally up to you what ratio you want to use. If you want to use a 1:6, if you want to use a 1:8, if you want to use something crazy like a 1:7.3, you can do that. You can go even lower than that too, like a 1:4, that’s. The only thing I’ll caution you on is that if you go super low and you start getting into some super sharp and angular dovetails, you’re going to end up with a fairly weak area at the very tip of the tail, because you have all the grain running vertically. As you’re trying to put your dovetail together, it is very easy to break the corners off.
Now we’ll get into actually making the jig. I have a piece of plywood here, but you can use literally whatever you want.
The only thing you want to consider is the length of the piece you’re using. This is going to vary depending on the size of your bandsaw, but you want enough length that you can grab the jig from behind the fence as you’re working. So the distance between the end of your fence and your blade is going to dictate how long this thing should be.
Since I already have a 1:8 jig, I’m going to make a 1:6. I’m going to come up six inches and mark that out. I know I want to be an inch away from our line to get the slope so, I will make a mark to an inch out from that line, then connect those to get the correct slope.
Now we just need to cut that line, and you can really do that however you want. You can use a track saw, you can use a miter saw, you can use a table saw, or you can use the bandsaw. One thing to remember with this is that the actual angle you cut on here doesn’t matter that much. If it’s a little bit off, it’s ok, because the use of this jig is for tails first. So whatever this angle ends up being, that is what your pins are going to get cut to.
The next thing we’re going to need is a little stop. For that I’ll use a little, tiny piece of hardwood which acts as a little stop to catch the work piece as you’re running this thing through the saw. I want that piece to be about the same thickness as the jig, and I’ll install it with a brass screw. The reason I opt for a brass screw is because if I get that screw into the blade, it’s not going to do anything to the blade. It’s totally up to you how long you want that stop to protrude past the end. I’m going to run it long and then cut it when I make the first cut with this jig.
Here is our completed jig, all ready to go! Now I’ll run through an example of how this jig fits into the general workflow. I’m going to cut some dovetails on the end of a piece of mahogany.
The process starts off exactly the same as any other kind of dovetail layout, so I’m going to scribe the length I want my tails to be. Now that I have my scribe line, I can work on my layout. What’s nice about this is that you really don’t need to do much layout, because the jig and the bandsaw do that for you. I’m going to put two tails on this piece of mahogany, so I’ll just mark those quickly. I just need to mark a center line so I know where to line things up for my center pin.
Over to the bandsaw. I set up my fence to make my first cut, and since I haven’t used this jig before, I’m going to cut through my little stop here, since I just want a little tiny nub of the stop left.
After making the first cut, flip the board to make the cut on the other side.
Next, I set up for the center cut, and it’s the same process. I will make that cut, then flip the board to make the cut on the other side.
From here, you can use whatever workflow you want to proceed with your waste removal. Typically, if my pin space is big enough, I’ll just do that right here at the bandsaw.
Now we have a board with tails on it. From here, I would lay my tails onto my pin board, cut my pins, and then fit my joint together.
If you do want to return to the bandsaw to cut your pins instead of hand cutting then, you can make yourself a little sled jig guide. Using the jig we just made as the basis of the sled, pattern route the exact angle to get an identical pair of these jigs, put a platform on top of one, and that’ll allow you to run your board on an angle through the blade. Then you can spin it around to hit the angle on the other side.
That’s going to do it for this one! Thank you, as always, for joining. I greatly appreciate it. If you have any questions or comments on hand cut dovetails, please feel free to leave me a comment. As always, I’d be happy to answer any questions you might have, and until next time, happy woodworking!