With the tails marked out, it’s time to start to make a bit of sawdust and cut the things out. There are two time honoured rules with these things which ought to be carved deep on a tablet of stone and they are as follows.
First and foremost, never cut them at the end of a long, tiring day. Second and foremost, always mark your waste! It has been known for a certain person, who shall be nameless but writes in the Woodworking section of The Knowledge, to disregard these two golden rules, much to his dismay on sadly more than one occasion.
Dovetails are tricky little blighters to cut, especially if you’re new to them, but you can make life a little easier by always sawing vertically, so the first thing to do is to tip the wood over in the vice and check it with a small square.
I prefer Japanese saws and have done for years, but it doesn’t really matter whether you like oriental or western; both will do the same job. Saw down to the shoulder on one set of lines, flip the wood the other way and then saw the other pair. I cut on the line so it’s still visible when all the sawing has been finished.
Next up is to remove the waste. I use a piercing saw to remove the centre pin waste and a Japanese dozuki to cut the two half-pins at the edges. There is a school of thought which says that you should cut spot on the shoulder line leaving nothing to clean up with a chisel. I never do because no matter how fine the saw tooth, the wood will still be ‘woolly’ and ideally needs to be finished with a sharp chisel. As I’ve cut them, there’s maybe 0.5mm to clean up on the shoulder line, which is easy enough.
Having produced the dovetails, the final thing to do is to chisel the shoulder line. I used to do this freehand for many years but, reading Rob Ingham’s rather excellent tome ‘Cutting Edge Cabinetmaking’, the easy way that he recommends (and it’s ridiculously easy) is to use a block of wood planed dead square. Simply clamp it onto the shoulder line, take an über-sharp dovetail chisel (a 3mm one is needed for the centre pin) and hold its back firmly against the block of wood. Push down vertically to leave a really crisp, dead straight shoulder line.
If there are any bits of fluff, whispers of wood or small areas that need to be fettled a little more, I use a very fine carving knife, similar to this one just to clean up the joint surfaces.
The dovetails is now done and dusted and, if everything’s gone according to plan, it’ll look something like this.
With the first half of the joint finished, the next step is to mark out the pins from the tails.