Daily production notes on projects under construction at Smoky Mountain Woodworks. Slip on a pair of safety glasses and come on in!
Tuesday, March 9
The Scary Part
In this step I will take those beautiful, wide, perfectly jointed boards I made up a while back and cut them into little pieces. (cringe). But not only will I cut them into pieces, but the pieces will have to fit together to form the octagonal-banjo shape of this clock. That means very precise angles need to be cut on these wide panels. And, I want to keep the grain flowing around each joint, so the pieces must be cut sequentially off of each board and with as little waste as possible.
I start by trimming the glued-up boards to width so the long edges are parallel. I will need to flip the boards over to cut every other miter, so they need to square-up from either edge.
I take a very light cut pass over the jointer to make sure the back edge is straight.
To make registering the side pieces against the back plate and holding them in place during glue-up easier I will cut a shallow rabbet along the back, inside edge of the sides. So I set up the dado head for a ¾ inch wide, 1/8 inch deep cut.
I really don’t like maneuvering such long boards through a cut like this all by myself, but I don’t have much choice. I install the long fence, and some fingerboards to help guide the plank, but keeping it flat on the table top so the cut is of consistent depth will be important – and difficult.
When I’m done, I have a very nice, even rabbet along the edge of both boards. One end of one board lifted on me just a little as it passed over the cutter, but I caught it afterward and cleaned it up with a wide chisel.
A good part of this day will be spent changing over the table saw. I remove the dado head, install a high performance blade and set it to the first of several angle settings.
If the “belly” of the clock were perfectly octagonal I could use a setting of 60 degrees for all the joints, but because the sides slope in at 2 degrees, I will also have one joint on each side at 58 degrees and another at 62 degrees. These angles must be cut on the ends of both pieces coming together at that point, and I must be sure I keep track to which edge is which. Any mistakes will result in tossing the side piece out, making a new one and starting over.
I install the wide cross-cut sled and set up to make my first cut. Say a little prayer and here we go…
When I get to the little pieces that angle out, I remove the sled, set up the rip fence and feather board. Because I’m cutting these parts in between larger parts this change over is done several times as I go from the lower side, to a small wing, to the side piece to a small wing, to the upper side. I am, however cutting the pieces for both sides as I go. That helps.
As I cut the pieces, I use clamps and tape to affix them to the back plate, building up from the bottom.
At day’s end both sides are completed, nothing has been glued yet, just being held together temporarily as I fit them together.
Here is what I meant about getting the grain to flow around each joint. It takes a lot more work than just cutting random pieces, or even cutting oversized blanks out of a single board and trimming them down. By wasting as little as possible in cutting the joints we get a very nice “flow” down the side of the case.
Next time we’ll begin gluing the pieces together. That too will be a challenge because the odd angles are hard to clamp and I can’t use nails or screws here because I will need to be ripping these side panels lengthwise to get the 4 degree front-to-back slope before I glue the sides to the back. That too will be tricky. We’re just having all kinds of fun on this project!
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