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Discussion Starter #1
First I know wood will expand and contract. However my brain took that day off when I made 2 boxes (13"Wx10"Dx7"H). I used Maple for the boxes. The wood is 1/2 inch thick and was sitting on my shelf for 5 years.
Bottom is glued in on 4 sides (1/2"thick) My question is - will boxes survive movement or should I go ahead and cut the bottoms out and fix the problem. These are Christmas presents and I need to do something soon.
Thanks RLH
 

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The wood will be at your present shop humidity. For a 13in wide dimension the amount of movement may not be large, perhaps 1/20in - 1/10in depending on the summer humidity of the final location.

Hard to tell if the bottom will pull away from the sides. Perhaps not initially, but could eventually.

If you want piece of mind I would take apart and make the bottom to be free floating in grooves along the sides.

This site is useful to estimating wood shrinkage/movement.

http://www.woodbin.com/calcs/shrinkulator.htm
 

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Depending on conditions, you may get away with it.

If the lumber was stored in an unconditioned building, expect 11 - 12% moisture content, which can go down to 6-8% in an air-conditioned home through the seasons. The base my warp ever so slightly, due to it being constrained.

As it is already built, I would leave it, but change my design for the next one.

I always build for completely extreme conditions, just in case someone moves to Arizona from the tropics, or the other way around.
 

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Wood will expand and contract across the width. Hard maple is a species that doesn't move quite as much as others. The fact that it has been sitting for so long may be a good sign, depending on the conditions in your shop. If your shop is heated, you probably would see the effects by now. Once finished, depending on what you use, that could help mitigate moisture absorption going forward. The worry would be more about shrinkage. End grain to face grain doesn't hold glue lines very well and it's possible that the glue line will break and not show ill effects like expansion would, pushing the corners apart. If you used KD cabinet grade lumber at about 8% moisture content, that would also be in your favor. Getting the boxes apart could be difficult and something might get broken. Hard to tell without seeing the boxes and your construction. You may be lucky, do you feel lucky, do ya? You might get a pass on this one.
 

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The amount of movement will vary depending on the difference in humidity between your shop and the future home of you project. I live in a dry climate. Wood that has been in my shop for awhile reaches a moisture content of 5-6%. I generally don't see much movement if a piece of my work is in someone's heated home.

I once was hired to build some cabin doors for a large sailboat. They were made of teak and were large enough to easily walk through. I was not sure how much movement I would see but I anticipated that the solid door panels would expand. I allowed 3/8" on each side for 3/4" total in a 21" wide panel. Was I ever glad that I did that. There was a lot of expansion. The boat owner hired another woodworker to build some cabinets in the boat. I felt sorry for him when all the doors he made "blew up" after the boat was in the water. He obviously did not allow for enough expansion.

Bret
 

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Discussion Starter #7
Thanks for the comments, believe I'll roll the dice and let it be. No sign of problems yet.
Again thanks:thumbsup:
RLH
 
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