Newbie question!

[Locutus]

Hey guys, new to woodworking, I own a store and I built a decorative deposit box on the inside of my office door with a mailslot on the other side.

The box turned out great, however after a couple of weeks, the door on the box warped and would no longer close right, it also looks like the sides drew in. I sanded the top of the door down so it would close and restained, however it no longer looks as nice as it did when I first finished it. I used large peices of laminated pine from home depot (24" x 36", 3/4" thick) and used a minwax gel stain after cutting but prior to assembling.

I plan on building some additional cabinets, and I am curious what I can do to minimize this problem in the future?

Any advice is appreciated, thanks!

[professorpaul]

I'll bet the issue is "the mail slot on the other side." Perhaps letting in moisture from outside?

I wonder if something laminated like plywood would be a better bet?

Thoughts from the group?

BTW, the advice for the latches for the table leaves someone suggested works great. Put them on last night. That sucker will never come apart in the middle of a dinner party again!

[Stephen M]

A picture posted to ABPW would help a bit.

....

Laminted pine will behave more or less like a lingle slab of pine. unequal exposure to moisture/relative humidity will cause it to cup. You can mitigate this coating *both inside and out* the stained wood with poly or some other film finish. (spar varninsh would be better for an exterior application).

Frame and panel construction rather than a single slab would be much less prone to warping. (Individual pieces of pine will warp just as much, but F&P construction does not make wood movement "errors" cumulative)

-Steve

[Locutus]

Sorry, I should have been more clear, its an interior office door, not an exterior door. The moisture should be the same on both sides.

Thanks.

[brianlanning]

It wasn't dry. Or rather, it was less dry than the room where you put it. It warped as it dried. In the future, you'll want to use kild dried lumber for this reason. There's not much you can do about it now.

brian

[mcnutt]

Be sure to finish your work inside and out so that all sides are sealed, not just the outside. Leave your stock in the workshop for a couple of weeks so that it gets used to being indoors. (The moisture content can stabilize.) Attach battens (cross pieces) to the underside of boards that are not supported on all four sides.

Just a few thoughts.

Bill

Locutus wrote:

[Locutus]

Thanks, I thought that might be the case. It's not a big deal on this piece, but I want to prevent it in the future. How can you know if lumber is kiln dried? I didn't see any such thing at Lowes or HD.

[Odinn]

On 2/9/2006 4:40 PM Locutus mumbled something about the following:

If you bought it at Lowe's or HD, it may have been kiln dried, but I've seen their lumber sit out in the rain for a week (usually just a tarp to keep it from being rained directly on) before even being brought in. For construction lumber, this isn't too bad (it's not good though), but for building cabinets and such, you want it to be very dry, especially if it's going inside where the air is conditioned, before you start working with it.

[steve.cormier]

You might buy yourself a moisture meter to see how dry the wood is. Also, it can be good to mill the wood just slightly larger than final, let it sit, then mill again to final dimensions. That way it will warp as it dries to final (well not really 'final' but much drier) moisture content, and when you mill it again to final dimensions, you have much more stable and once again square stock.

Even if you let it sit and it's not close to final dimensions, when you cut it (especially if you resaw) it may then warp because it's moister in the center than at the outside.

You might also choose a more stable (though of course more expensive) hardwood like cherry or walnut instead of pine.

[Stephen M]

Attach battens (cross pieces) to the underside

I think that's dangerous advice. A batton across 24" of wood shouldn't be secured across the grain without allowing for some movement (like slotted screw holes on the ends). To simply glue a batton of that length, across the grain is not good practice.

-Steve

[brianlanning]

As odinn said, it's hard to know since it may have been rained on. The independany lumber mills I've seen keep the wood in sheds after it's been through the kiln.

Most construction type lumber at the big box stores, this would include things like cedar or the bigger 2x10 or 2x12 boards, is S-dry. This means that it's dry but not really that dry. I'm sure that someone can chime in with percentages. S-dry isn't really green, but it's still wet enough to warp. The s4s oak boards you see there, and the boards next to it are probably kiln dried, although they may still warp.

brian