Wood Problems

[Paul Douglass]

I have been buying more wood in various species from places like Ocooch Hardwoods, Cherokee woods, usually in 1/2" or 1/4" thickness. Plan on using it for clocks and boxes, etc. When I get the wood I open the package and stack the wood with strips of wood between layers, to let it Climatize for a couple weeks, Hoping to prevent cupping and warping... I get very little warp, but 90% of the time I get cupping. I need suggestion on how to prevent this from happing, or how to correct it when it does happen. I have tried to dampen the concave side (wrong side, maybe?) and let sit undeer weight until dry, Than a youtube video suggested heating the convex side until almost scorching then let cool. I have had very little success with either.

Just curious if there is a prevention or a remedy. You guys handle the exotic/ domestic hard woods more than I do.

 

[Brian McMillan]

Put a damp towel (not soaking wet) on the concave side then iron it for a while with a hot iron. I use mine on the steam setting. Clamp cauls across and leave it over night. You may have to do it a few times.

 

[Darren Wright]

I was about to suggest, maybe a steam iron to heat and flatten it? let it cool back down under weight

 

[Ted Calver]

I used to stack and sticker like you have already done, but then tightly wrap several layers of shrink wrap tape around the bundles everywhere there was a sticker line. Worked for me.

 

[Mike Stafford]

I used to stack and sticker like you have already done, but then tightly wrap several layers of shrink wrap tape around the bundles everywhere there was a sticker line. Worked for me.

Just like Ted I always stacked and stickered thin stock that I bought or that I made by resawing and planing. When I stacked the wood with stickers between layers I always topped it off with a couple of 10 pound barbell plates to aid in convincing any unruly wood that bad behavior would not be tolerated. Sometimes it took weeks or months for the woods to acclimate and stay flat. The time was dependent on the origin of the timber. Exotics, in particular, could be quite difficult to control in my high humidity/high temperature locale.

Whenever you expose wood to a new environment by moving it from one part of the country or world to another or by planing and exposing interior grain it is almost always necessary to "train" the wood to behave.

P.S. This technique will not work with twisted, warped, cupped woods from big box stores.

 

[Ted Calver]

Note. These techniques will not work for apple wood....nothing does

 

[Ryan Mooney]

Note. These techniques will not work for apple wood....nothing does

Pear has similar opinions and until it's settled down lilac agrees (once lilac has done it's thing it's pretty stable though).

 

[Mike Stafford]

As an aside, when I turn exotics for boxes I always rough turn the blank by partially hollowing it. Then I let the top and bottom sit taped together tenon end to tenon end. Just like exposing new wood to a different humidity/heat environment by sawing or planing, turning does that as well, particularly when you are hollowing.

By doing this I have seen as much out of roundness in the end grain rough turned box as 1/4" in a 3 1/2" blank. Some woods are worse than others. The final wall thickness of the box is also a consideration.

Wood continues to move even when it is kiln dried. I live in a very hot and humid environment and boxes which fit perfectly at my house change when they get to Minnesota or Hawaii. The fit may become more loose or so tight that it take a lot to open one.

One of my favorite Roy Underhill stories is about the time he was visiting Japan and was with a master carpenter who made beautiful sweater boxes with sliding lids. These boxes were held together with dovetail joiner and no glue and the lid fit perfectly into grooves in the sides and back.

Roy was so impressed with the perfect fit of the lid and commented to the master that the lids must swell up and be stuck during the hot summer months. The Japanese master carpenter said, "Yes, that is true but I don't need my sweaters during the summer."