There’s a trick to cutting perfect dadoes by hand: cut thousands of them. In the meantime, on the way to that perfect dado, you’re going to cut a few that are just a hair too loose or too tight. My sin is always to get nervous and cut them too tight. I abhor a sloppy dado.
These tight squeezes are pretty easy to fix with a block plane on the joining piece if it’s a shelf or something of that nature, but occasionally making the mating piece thinner would have adverse affects on the rest of the joinery. Such was the case for me this week with the second shaker dining bench I’m building.
The bench is held together by essentially creating an egg-crate joint between the legs and the seat stretchers. It’s rock solid if it’s cut right; wobbly if not. The stretchers sit 1/4 inch below the top of the legs to allow a 1/4″ dado in the bottom of the seat to lock everything into position. Long story short, when I cut the dadoes this week I didn’t make them quite wide enough to slip down over the leg pieces. Going back to plane the leg pieces thinner would have caused the joints with the stretchers to wobble. You see the dilemma.
It was literally the width of a saw kerf separating too tight and just perfect, so this is how I fixed it. I’m only showing this because it might help someone out.
- First, get a piece of squared off hardwood that easily slides into the dado.
- Lock it in place like a batten with a few wedges, just tight enough to keep things from wobbling.
- Hold everything down with a holdfast and use a block to keep the saw right against the batten at precicely 90°
- Saw like you’re holding a Faberge egg.
Here’s what that looks like:
(Here’s a trick. Put sandpaper on the bottom of the guide block.)