# Wood Movement



## Quailguy (Feb 20, 2015)

I am building a hanging tool cabinet for my shop. The door is a dovetailed frame rabbeted to accept the 3/4" mahogany door panel. This panel will not be glued, but held in with tabletop Z clips. The panel slips into place with slight pressure, meaning I don't have to bang it in, but I do have to exert a small amount of force. Here's my question; how much space do I need between the panel and frame to allow for seasonal movement? The panel is 35" tall by 24" wide, made up of 5 edge glued boards.

Thanks in advance
Mike


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## jumbojack (Mar 20, 2011)

There are so many factors to determine wood movement. The moisture of the lumber and the relative humidity. If your panel is say 7% during the dry part of the year and you live in a humid area you could see 3/16" over 24" with Mahogany.


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## pintodeluxe (Sep 12, 2010)

1/4" is a good rule of thumb (1/8" on each side). Go to the shrinkulator and type in the lumber species, type of milling ie quartersawn / flatsawn, and relative humidity variations you expect to get for a more exact number.


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## Quailguy (Feb 20, 2015)

Is there a "rule of thumb" that I could use to prevent the frame from distorting? Would I be safe in leaving a 3/32 +- reveal around the panel to allow for the movement? I don't think that small of a gap would affect the aesthetics.


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## Quailguy (Feb 20, 2015)

Never heard of the Shrinkulator, great tool. I'll go with the 1/4 inch. I'm in Southern California so we get very little 90% days and average about 15% to 70%. Because the panel is removable, I can resize it if necessary.
Thanks to all


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## JBrow (Nov 18, 2015)

Quailguy,

I am with you. I have never heard of Shrinkulator, but I now have it book marked. Thanks pintodeluxe.

I am sure you are applying a finish to the panel before installing it, but I thought I would mention this important step anyway. A finish with reduce the rate at which moisture enters and leaves the panel and therefore should reduce any seasonal movement.


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## Quailguy (Feb 20, 2015)

I am going to use shellac at least, not 100% sure if anything else. I went ahead and planed about 3/32's from each side as a precaution. It actually gave it a nice reveal. This is my 1st attempt at a large dovetail project with sliding dovetails and other techniques I've never tried before. I'm being extra cautious as I'm not in a hurry. 
Thanks for the advise
Mike


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