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devil duck


Scene 1: night, a street in a residential neighborhood of New York City, lit by the occasional streetlight. A man and a woman are walking their greyhounds, and they notice a large styrofoam cooler left out on the corner for trash pickup. It seems in good condition, and reasonably clean, so they take it home and adopt it.

Scene 2: some years later, they take the styrofoam cooler to Pennsic, pre-loaded with a 22-lb. block of dry ice. It lasts for about five days, and they conclude that a cooler with dry ice is a Good Idea. If only it weren't so ugly and blatantly modern-looking...

Scene 3: on the way home from Pennsic, they stop at a pizzeria to re-enter modern society and make a list of projects for next Pennsic. One of them is building a wooden chest around the styrofoam cooler.

Scene 4: I'm not a terribly proficient woodworker, so this will be a six-board chest. I've done that before, but this one will require techniques I haven't done before: gluing boards edge-to-edge, fitting boards into grooves and dadoes, etc.

I measure the styrofoam cooler, measure the various bits of lumber lying around, and conclude that two pieces of unfinished 2"x8" side by side are exactly wide enough for the ends, while two pieces of finished 1"x8" side by side are exactly wide enough for the bottom and sides. The top needs to be a little wider... maybe a 1"x8" and a 1"x10"? The seam down the middle will be slightly asymmetrical, but if I put the hinges on the edge of the 1"x10" side, it'll be less noticeable.

I spend a couple of evenings cutting boards to length, planing their surfaces even, squaring their edges, etc. and then start the edge-to-edge gluing. Each edge has two holes drilled into it, into which I put glue-covered 2-1/2" pieces of dowel; I also glue the rest of the edge, then clamp the boards together to dry. In this manner I make a bottom panel, then a side panel that turns out to have been mismeasured and to be another bottom panel instead, then two correct side panels, two end pieces (of 2" stock), and finally the asymmetrical top panel.

I cut a rectangular chunk out of each side of each of the almost-2"-thick end pieces; the side pieces will eventually fit into this gap. Three of the four come out cleanly...

... and one doesn't: I've sawn a bunch of cuts, to roughly the right depth, but as soon as I start chiseling away the stuff in between, the chisel dives below the cut line. And keeps doing it. The obvious answer is to chisel from the other end, so the grain is sloping up rather than down, but the other end is blind, which makes things trickier. Fortunately, this surface will be covered by another piece of wood, so as long as it's not too high at the center or too ragged at the edge, it won't look too bad.

The way I calculate it, I need 3/16" deep grooves the length of each of the side panels, for the bottom panel to fit into. I'd prefer a deeper groove than that, but the bottom panel is only so wide. I've never tried this before, and all the woodworking books talk about routers and rabbet planes and things I don't own. So I run a sharp knife along a straight-edge on both sides of the groove-to-be, reinforce this cut by banging a 1" chisel into it, and start chiseling away from the end. It works surprisingly well, although it's a pain trying to get the whole thing to a uniform depth.

And this is what happens when I fit the bottom panel into the groove in the side panel. The groove isn't deep enough to really hold it in place, but it'll be glued eventually, so let's go on.

The bottom panel also needs to fit into a groove in the end pieces... except that since this groove is across the grain, it's called a "dado". (Words like "dado" and "rabbet" are used a great deal in woodworking books, but seldom defined....) This calls for a different technique, which again I've never tried. And again, I don't have a lot of fancy tools, so I use the cross-cut saw to make two parallel 3/4"-deep cuts, then chisel out the wood in between them. Again, it works pretty well, although getting a uniform depth is a pain.

So now everything can be fitted together. The side panels don't want to stay in place, because the grooves holding the bottom into them are so wimpy, but this will be glued eventually so no problem. And suddenly it occurs to me: the grooves in the side panels really shouldn't have gone all the way to the end, because the bottom panel that fits into them doesn't. You can't see it in either of these pictures, but there's a 3/4" high, 3/16" wide gap near the bottom of each side panel where it meets the end panels. I don't know what I'll do about this; deal with it later.

A bigger problem is that the end pieces, after planing to clean up their edges, have turned out slightly narrower than I intended them to be, so the bottom panel sticks out too far to fit into the grooves in the side panels, so there's a substantial gap between each side panel and the end pieces. I was worried that this would also prevent the styrofoam cooler from fitting in, but it just barely makes it.

So I shave down the edges of the bottom panel with a plane so it fits between the side panels. In fact, it fits too well: there's almost no wood sticking out to fit into the groove. Hmm... wasn't I lamenting that the grooves were too shallow anyway? I really should have deepened the grooves instead of shaving down the bottom panel. As luck would have it, I still have the spare bottom panel I made by mistake several paragraphs ago, and it's still full width. So I go back to chiseling, converting the earlier 3/16"-deep grooves into 3/8"-deep grooves.

I mostly avoid compounding the earlier mistake of taking the grooves all the way to the end of the side panels: I deepen them only up to 1-1/8" from the end. So there's still a visible hole at the ends, but no worse than before.
I've also learned that if you want a 3/4"-wide groove, you don't use a 3/4"-wide chisel, because it kicks up enough chuff at the edges to make the groove a bit too wide. Instead, you use the 3/4"-wide chisel from a different brand, which is actually about 11/16" wide. So now the grooves and dadoes are snug enough that the chest more-or-less holds together by friction alone.

And the styrofoam cooler still fits into it. There are slight gaps at the tops of two of the side0-panel/end-piece joints, but much less than before.

Still to do: handles or battens?; gluing (and pegging or nailing?) everything together; ornamental cutouts at the bases of the end pieces; attaching the lid; finishing all the surfaces.
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The top needs to be a little wider...

I *really* don't think it does--my recollection of the photos of extant six-board chests I've seen is that the top edges were flush with the sides.

And it wasn't "some years ago"--we found that cooler within the last year. Ah, yes--I remember it well....

Edited at 2010-08-31 08:15 pm (UTC)
1) The top would need to be 3/4" wider than the bottom even if its edges were flush with the sides, since the bottom only goes halfway into the side pieces, while the top must completely cover the side pieces.

2) I looked at a bunch of chest pictures in our historical-furniture books this afternoon. Some chests have lids that are flush at the ends and the side. Others overhang at the ends, but are flush at the side. Others overhang at both ends and side. I found multiple examples of each of those three combinations. There seems to be a tendency for the really big chests to be flush, and smaller ones to have more overhang (although there's a c1440 illustration of a platform bed whose "platform" is a bunch of top-opening compartments, and it has overhang at both ends and side). There's a coffer whose dimensions are almost exactly those of the current project, and whose flat lid overhangs in both dimensions (although it's 16th-century, and paneled construction rather than 6-board). I'll have to do some more checking to see if there's a real correlation with size, or 6-board construction, or century.