People need food and stick chairs need wedges. They say that there are as many recipes for Spaghetti alla Carbonara as there are Italian housewives. I say there are at least three good ways to make wedges. None of them unfortunately include either pancetta nor Pecorino Romano, but you can’t really expect that from wood. In a mini series of three blogposts, we (Chris, Rudy and me) will share each our way of making them.
To make wedges with a band saw, you need the following:
A randomly sized scrap block of wood (in this case some 24mm Birch ply). Another scrap block of wood with the grain going more or less perpendicular to the long sides. The latter is important, as a wedge with cross grain will be hammered into mush by the first whack from the lump hammer. You also need a knife. And a pencil. And, of course, a band saw. Duh.
The largest block of wood is for the jig. Start by drilling a hole in it. You’ll use it to push and pull the block when you’re sawing out the wedges. It’s not necessary, but unless you’ve got sticky fingers (I don’t wanna know why!) by default, it makes things both easier and safer.
With the hole drilled, it’s time to mark out the size of a wedge onto the jig. But first, make sure that the scrap wood you’re using for the wedges is the size that you want it to be. Its thickness needs to be slightly more (1/16″ is enough) than the diameter of the mortise. So if your mortise is 5/8″, I’d aim for a wedge that is just a tiny bit wider. That way the wedge won’t leave a gap. Second, the block needs to be as wide as you want the length of your wedges to be. When wedging chair legs, I keep the wedges at around 1-1/4″. When I’m wedging short sticks for the arm, I usually end up at around 1″ length. You’ll figure it out.
Use the wedge block itself to mark out a wedge on the jig, by skewing it a bit in over the edge and drawing along its edges.
I usually make my wedges around 1/4″ thick at the top.
With the wedge shape drawn up, cut the notch out. Be accurate. If you make a wonky notch, you will have wonky wedges.
Use the fence to position the jig block toward the band saw blade. You’ll slide the jig back and forth between the fence and the blade so it needs to runs freely, but as close to the blade as you get it. Set the blade guide as low as possible to ensure precise cutting.
Start the band saw. Push the wedge block into the notch as shown above and push forward toward the blade. Push all the way through and pull back. You’ll soon find out that if you do this carefully, the wedge will be neatly pushed out to the right side of the blade when you pull the jig back – getting you ready for the next cut. Flip the wedge block over and you will square it off when cutting the next wedge. Pull back, flip again and on you go. You are now a Human Wedge Making Factory™. Be sure to make a bunch while you’re at it!
Finally, before using the wedges, I like to sort out the best ones. Which are the ones with the straightest grain and the most consistent shape. This is also where the knife comes in. To make it easier to hammer the wedges in, I taper them a bit with my knife. That way the wedges won’t bruise the edges of the mortise and they’ll enter the kerf easier.
That’s it! Time for that Carbonara.