bowed panels

[John-Paul Volkenant]

I'm building a tool chest with dovetailed panels. Each panel, since being glued up from 3/4" pine, has developed a bow, more or less. I expected this, and its not that big a deal to me, though I could be underestimating the problem. Anyway, my plan was to have the concave side of the panels face the interior of the chest. But, after thinking about it a little more, and reminding myself there will be a dovetailed skirt around the base and the top (the dust seal), I wondered if it would be better to place the convex side inward, where the skirts will reinforce the top and bottom dovetails, should they begin to pull away. I hope I explained this well.

Or, because I'm gluing the dovetails, does it even matter? I was just thinking that if those dovetails in the middle of the panel started pulling away, there would not be anything to back 'em up.

Thanks.

JP

[Mel Fulks]

Dont think the bow is going to matter , with pine I would put the bark side on the outside of the box. Sometimes you can flatten a panel by putting in on a table convex side toward the ceiling and see it straighten in just a few hours.After it straightens lean it against something in a way that exposes both sides to air.

[Stanley Covington]

You call them dovetailed panels, but do you actually mean boards?

You don't mention how big a bow or deflection over what distance. If it is small, no big deal. If it is large, you might want to straighten them out if only to see if they will warp again. If they tend to warp easily and a lot, the spacing/size of you dovetails may need to be adjusted to ensure the corners are still tight when your Grandkids inherit Grandpa's toolchest.

The easiest way to straighten them in hot summer months is to put the boards cupped side down on the lawn with the sun heating their backs. In colder months, laying it down on a wet blanket in a warm room with a heat lamp on the back works well too. Don't let the endgrain get soaked. Check the MC of the boards before you do this. After the boards have straightened out set them aside on edge and on stickers in a room temperature/dry room and let them acclimatize to the same MC as similar wood species inside your house. If they stay straight, all is well. If not, you need to make some difficult decisions. One possible decision (perhaps the best) is to make new boards from more stable material. Quartersawn if you can get it.

You can straighten out boards with fire on a barbecue too. This is quicker, but it is a bit dangerous and is best done on thicker boards and before planing since it tends to discolor surfaces. Also, the heat can damage glue joints, so it only works on single boards.

If the boards warp again, and you decide to use them anyway, use lots of dovetails and space them tightly. Repeat whatever straightening method worked for you the first time until the boards are flat. I would put the cupped surface inside the chest. Layout and cut the dovetails before the boards warp again. Since the boards are only 3/4" thick, you can force-straighten the boards with clamps for glue-up so long as the warp is not severe enough to cause cracking when the boards are straightened out. But it is better to glue the carcass up while the boards are straight. If your chest walls are not too long, the cupping that tries to develop later will be constrained and not detectable without using a straightedge.

Not the most elegant way to get the job done, but it will work fine.

Stan

[Jim Matthews]

Do the joints close, when assembled?

The point of wooden tool chests is to maintain a more stable humidity level inside the chest.
The panels will move with the seasons as the wood absorbs and releases moisture.

If the box is solid, and the joints close what's the worry?

[Mel Fulks]

I thought you were concerned about just having them flat enough to work on before assembly. Yeah ,once it's assembled it will be fine.

[Jack Curtis]

...After the boards have straightened out set them aside on edge and on stickers in a room temperature/dry room...

I've never tried this racking method, but only because I can't imagine stickers would be useful between edges, very cumbersome layout. The rest of it is a pretty good method.

[Stanley Covington]

I've never tried this racking method, but only because I can't imagine stickers would be useful between edges, very cumbersome layout. The rest of it is a pretty good method.

The stickers in this case just ensure you get air circulation at all surfaces of the board to help the wood dry out and reach equilibrium quickly. Of course, you can't dimension the wood or cut the joints until the wood has reached, or is at least very close to, equilibrium.

Stickers are a good idea even when stacking dry lumber. I am sure you have pulled a board from a nice neat stack of wood, set it aside for a time, and have it warp. Stickers can help reduce this.

[Mel Fulks]

Stanley's idea is good ,but more necessary on air dried than kiln dried. We always stacked the panels until installation and the panel on the top would keep moving . When you walked by them an saw top one rolling up you just flipped it over . Sometimes a pc of plywood would be put on the top of the pile. I have never had a raised panel open up on the ends.

[Jack Curtis]

The stickers in this case just ensure you get air circulation at all surfaces of the board to help the wood dry out and reach equilibrium quickly. Of course, you can't dimension the wood or cut the joints until the wood has reached, or is at least very close to, equilibrium.

Stickers are a good idea even when stacking dry lumber. I am sure you have pulled a board from a nice neat stack of wood, set it aside for a time, and have it warp. Stickers can help reduce this.

I thought I was clear. I understand everything about stickers, just don't see how you use them to stack wood on edges. Fairly impossible, I'd think.

[Stanley Covington]

I thought I was clear. I understand everything about stickers, just don't see how you use them to stack wood on edges. Fairly impossible, I'd think.

Sorry. My explanation was inadequate. Lean the boards on edge against a wall with two stickers on the bottom to keep them off the ground.

A lot of lumber is stored this way here in Japan, so I just assumed it was understood.

Stan