With the pin board marked out, now comes the precision bit…sawing the waste. It’s necessary to saw accurately on the waste side of the line, stopping on or just short of the shoulder line and it’s something that requires a little bit of practice. If you find some difficulty in doing this, it’s well worthwhile practising on some scrap wood. With the vertical lines sawn, the waste should be sawn out, leaving around 1mm or less to chisel.
Exactly the same technique as before is used to finish on the line, only this time a larger chisel and hammer are needed. Note that the pin board is cramped face side upwards, so that the shoulder line that’s chiselled will be on the side that shows. This means that any slight discrepancy ought to be on the inside, where it’s not quite so critical.
At this stage, the bottom of the pins can be cleaned up if necessary with a small, very sharp knife. A scalpel works quite well, but the blades are altogether too fine and you’ll find they snap at the drop of the proverbial chapeau! Some years ago I bought a very old cut throat razor and used the blade to make this little knife which I then epoxied into a very crude ash handle.
If you ever want to make small cutting knives like this, I recommend trying to get hold of an old wet cut throat razor as only the finest quality steel was used to make the blades. You’ll also find that if you go down to your local second hand tool emporium, or even something like a boot fair, you can probably pick one up for a song.
Once the pin board has been finished, use a small hammer and block of wood to tap the joint together. It should fit with the minimum of effort and there should be a small projection on each of the faces, which can then be cleaned off with a finely set smoothing plane.
Once complete, the final joint can be left with or without the shoulder lines. I’ve left them in place in this example but it’s up to the discretion of the maker whether they’re removed or not.
If the dovetails are used, for example, at the back of a drawer, then the shoulder lines could reasonably be left in place, but where it’s a ‘show’ joint they should be removed.
This is a small box in English walnut that I recently finished as a gift for my brother’s 60th birthday. You’ll clearly see the dovetails at the corner, with the shoulder lines planed off. To leave them in place in a project like this would be completely inappropriate.
Here endeth the lesson on making a through dovetail joint, but if you have any queries, please don’t hesitate to leave a comment or three below.