Don’t Blow it on the Lid

Lid-1

Miters and mayhem. The flat panel lid warped and shrank. The miters lost their hold. This lid is a mess.


This is an excerpt from “The Anarchist’s Tool Chest” by Christopher Schwarz. 

There are several ways to make the lid. Some work great. Some are quite stupid. Let’s start with the stupid ways first. When I built my first tool chest, I copied the construction of the lid from an original. It was a single flat panel of wood trimmed on three of its edges with narrow stock that would interlock with the dust seal attached to the shell.

If I remember correctly, I think the lid worked as intended for about a week, and it has been bockety ever since. The first problem was with the lock strike, the brass plate mortised into the underside of the lid. Because the lid was a simple flat panel, the top shrank a bit, which moved the lock strike.

One day I tried to lock the chest, and the mechanism wouldn’t engage. In fact, it just pushed the lid up off the dust seal. So I filed the opening in the strike until the lock worked again. About six months later the top expanded and the lock wouldn’t work anymore. This time, filing wasn’t going to fix the problem – I would have filed away one wall off the strike. So I resigned myself to having a chest that would lock only during the dry season.

Then the top warped.

Because the top of the lid was the bark side of the tree, the warping made things worse. The front and back edges of the top curled up. And the movement was enough that the strike couldn’t be struck by the lock mechanism.

But my troubles didn’t end there. When I built the chest, I wasn’t a total doofus on the topic of wood movement. I knew the lid was going to move, so I selected a species that didn’t move a lot once it was dry. I used white pine. And when I applied the trim around the lid, I did everything I could to minimize the problem of cross-grain construction. The trim pieces on the ends of the lid were the problem. They had to be nailed onto the end grain.

This is a problem. Nails and screws don’t hold as tightly into end grain as they do into face grain. So I wanted to introduce some glue into the joint to help things along. of course, glue doesn’t want to stick to end grain. And when you glue long grain to end grain, the end grain will try to bust apart the joint as it expands and contracts with the seasons.

There are several solutions to this problem. Some involve a sliding dovetail. others involve screws in elongated slots. The simplest solution is to glue and nail the trim on at the front of the lid and use nails only at the back part of the lid. This was the technique that the original builder had used. The theory here is that the glue and nails will keep the trim secure and tight up at the miters, and the nails at the back of the lid will bend to allow the lid to move.

It’s an interesting theory and one that sometimes works. It sure didn’t work for me, however.

The trim is barely holding on to the lid. The miters are open and flopping around like a broken finger. And the lid’s joints look like crap. I want to remove the lid and rebuild it. I should remove it and rebuild it. But I really like the way the paint has aged on the lid, and the broken joints are a constant reminder about the wily ways of wood.

So when I set out to build a new chest, I looked for other historical examples that would be more durable. The vintage pine chest I bought had the trim glued and pinned to the underside of the lid. This had the advantage of removing the end grain from the equation. All the joints were long-grainto-long-grain. But this is still a bad way to build a lid. Instead of the trim coming loose, this lid is designed to split. And boy did the lid split. There is a 3/8″-wide canyon right up the middle of the lid, which invites dust inside. It’s such a problem that the best solution was to cover the split with tape to keep the dust out.

So don’t build your lid like that.

I took a look at other chests. Duncan Phyfe (1768-1854) was a smart guy, one of the most celebrated 19th-century cabinetmakers. And his tool chest, now at the New-York Historical Society, is filled with all manner of amazing tools. But the lid is curious. It’s a flat panel with breadboard ends. While the lid worked out for Duncan, it might not work out for you. Breadboard ends definitely can help things and improve the way a dust seal will attach to it. But it still won’t help things when you add lock hardware. It’s going to move forward and back as the panel expands and contracts.

Lid-2

Better lid. A frame-and-panel lid with a raised panel is about as robust as you can get without adding lots of weight.

Really, the best solution is to build the lid as a frame-and-panel assembly (or use a slab of Formica). This confines almost all of the wood movement to the panel that floats harmlessly in the middle of the rails and stiles. And if you choose quartersawn wood for the rails and stiles, they will barely move at all.

So you could build the lid in the same way you would build a raised panel door. I would recommend using through-tenons on the rails. But what about the panel? You want the panel to be thick and stout because it will take a beating. So the joint between the panel and the lid frame is critical. You don’t really want to thin down the edges of the panel as you would when making a door panel. Thin edges will weaken the panel.

The old-school solution here is to plow a groove in the edges of the panel so the panel will interlock with the rails and stiles. This will keep the joint between the panel and frame as stout as possible, and the panel will be raised above the frame of the lid.

There is no downside to this approach. There are no weak spots on the lid. There is no significant wood movement along the edges or ends of the lid. So the trim around it will stay put. It is as permanent as can be.

Meghan Bates

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2 Responses to Don’t Blow it on the Lid

  1. KeithM says:

    I often tell people, “You cannot control wood movement — you can only account for it.”

  2. Jim O'Dell says:

    Great book. I just finished it a couple of weeks ago. It’s one of my new favorites along with Unplugged Woodshop. I also read your book on workbenches and I’m working on the Anarchist’s Design Book now and it’s been great. I grew tired of the typical woodworking book a long time ago. I don’t need to read about the fundamentals for twentieth time. While I’m sure there is something to be learned in every one of these book they just get boring quick. I love the way writers like Chris and Tom write because it’s not just about the technical details of woodworking. They write about life too. Chris’s attitude very closely resembles mine so I find myself chuckling quite a bit at a lot of his comments. If you haven’t read any of his stuff yet do it. You’ll end up spending too much money here at LAP and wont regret it for a moment.

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