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Forum topic by Quailguy posted 03-04-2016 05:31 PM 410 views 0 times favorited 6 replies Add to Favorites Watch
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Quailguy

33 posts in 654 days


03-04-2016 05:31 PM

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


6 replies so far

View jumbojack's profile

jumbojack

1667 posts in 2087 days


#1 posted 03-04-2016 06:03 PM

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.

-- Made in America, with American made tools....Shopsmith

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pintodeluxe

4853 posts in 2276 days


#2 posted 03-04-2016 06:16 PM

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.

-- Willie, Washington "If You Choose Not To Decide, You Still Have Made a Choice" - Rush

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Quailguy

33 posts in 654 days


#3 posted 03-04-2016 06:18 PM

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

33 posts in 654 days


#4 posted 03-04-2016 06:57 PM

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

View JBrow's profile

JBrow

818 posts in 382 days


#5 posted 03-05-2016 03:55 AM

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

33 posts in 654 days


#6 posted 03-05-2016 04:19 AM

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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