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Forum topic by woodman71 posted 06-27-2010 01:55 AM 1180 views 0 times favorited 6 replies Add to Favorites Watch
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woodman71

162 posts in 2790 days


06-27-2010 01:55 AM

I built this project had the door fitting great my shop is in the basement of my home . I didn’t stain it came back a couple days later and not pay any mind to door stain it . It was after I stain it that I noticed the door had cup and it would not stay close. I got up set a little and down about it . I’m know rebuilding the door but the real question is how many of you have to redo some thing on your projects and what do you learn from it and is it possible that stain will cause wood to expand I will have to say that having my shop in the basement of my home cant help to much for moisture . My next question is what do you think I could do to help with moisture will a dehumidifier make that much of difference . Also the door is 30 1/2 inch long and 8 1/4 wide the center of the door has dados in it 1/4 deep 5 of them and has 1 inch square thick post on the side . I thick that the center is ok it was just the hinge side post that cup . Its really got me down.


6 replies so far

View lew's profile

lew

11343 posts in 3221 days


#1 posted 06-27-2010 03:25 AM

I run a dehumidifier in my basement shop all spring, summer and fall. The winter doesn’t seem to create a problem as the heat tends to keep it dry.

-- Lew- Time traveler. Purveyor of the Universe's finest custom rolling pins.

View 8iowa's profile

8iowa

1546 posts in 3227 days


#2 posted 06-27-2010 04:22 AM

Woodworking author Nick Engler states that wood coming from lumberyards usually has a moisture content too high for immediate use. Construction type lumber sometimes has a moisture content as high as 30%.

Engler recommends letting wood climatize in your shop for at least a month during humid seasons and construction lumber should be stickered and allow to dry six months.

-- "Heaven is North of the Bridge"

View Catspaw's profile

Catspaw

236 posts in 3281 days


#3 posted 06-27-2010 02:14 PM

The simple truth is, you can’t really control moisture. No matter how good things are when you build something, the conditions will change.

Putting finish on one side (the “good” side) can cause in imbalance. But then I don’t like to glue finished surfaces together if I need to put finish on something before it’s put together.

Once it leaves the shop, things will change. A good finish willl be your best defense after the fact.

Letting the wood sit in the shop is best. Pick your wood and mill out all the warps, cups, bends, etc. If it changes after that, pick a new peice. There are some peices that you can accept like a flat bow on faceframe stock that you can tie down to the side. But, door parts and such need to be flat and stay flat. Trying to put something together that is not straight and hoping that you can “build” the straight into it doesn’t work. Those stresses wil come back.

Leave it in the shop, wait for it to do its thing, mill it flat, wait some more. Pick the straightest stock and go from there.

Dehumidifier is an excersise in futility, IMO, unless you intend to have it go with the peice you’re making.

-- arborial reconfiguration specialist

View Chiefwoodworker's profile

Chiefwoodworker

149 posts in 2844 days


#4 posted 06-27-2010 02:56 PM

Wood is hydroscopic, meaning it will always be ready to take on moisture or give it off. You can’t stop it. The trick is to let it reach equilibrium with its environment and that means letting it sit for a period of time until its moisture content is consistent with the temperature and humidity surrounding it. Of course if you let it reach equilibrium in a damp basement and build something from it and then move it to Arizona, well, good luck. You must take moisture into account when building something and a moisture meter is very handy for that purpose. They aren’t terribly expensive and they are quite accurate.

A finish, whether both sides or only one, can’t stop moisture from entering/leaving wood. It does slow it down however. And you can, as mentioned by catspaw, cause an imbalance and subsequent warpage when only finishing one side, though this can be self correcting as the moisture content reaches equilibrium.

De-humidifiers work great if you hook them up to empty automatically and let them run unattended. But that doesn’t solve the problem of moving a piece from one environment to a very different one. You have to consider moisture in the design. There have been many articles written on how to do this. A really good one appeared in American Woodworker, 1993 issue number 34. The title is Coping With Wood Movement – How to Build Furniture That Won’t Crack or Split, pages 38 – 43 and written by Jim Cummins. You can find it at http://books.google.com/books?id=r_YDAAAAMBAJ&pg=PA42&lpg=PA42&dq=average+indoor+equilibrium+moisture+content&source=bl&ots=Z8TKbnCLrP&sig=c72rDOeyaJm4pvvbBJ3lgjW0lC0&hl=en&ei=5JwjTPGBH8OB8gbF7_zIBQ&sa=X&oi=book_result&ct=result&resnum=2&ved=0CBcQ6AEwATgK#v=onepage&q=average%20indoor%20equilibrium%20moisture%20content&f=false

-- Joe.....

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Chiefwoodworker

149 posts in 2844 days


#5 posted 06-27-2010 03:45 PM

Whoops! I mean hygroscopic.

-- Joe.....

View woodman71's profile

woodman71

162 posts in 2790 days


#6 posted 06-28-2010 12:14 AM

Thanks every one woodman

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