Wood shrinkage issue

[Bill Hays]

I’ve just completed a Krenov style cabinet. It’s solid cherry joined with dowels. It has 9 drawers. The wood was thoroughly dry. My shop is in the garage where the humidity averages 50 to 60 percent. After bringing it into the 40 percent humidity house I expected some shrinkage and the closely fitted drawers to loosen up.
Nope. The 5 drawers in the center became difficult to move. The tightness is all on one side. I’ve pared them down and they get tight again. I’ve let the cabinet sit without drawers for a couple of weeks. The drawers are interchangeable. Any drawer sticks in those spots. Those drawers fit fine everywhere else.
I reason that the shrinkage caused the volume of the case to shrink. That’s new to me. Why in one part of one side? Wood is organic and, apparently, moves in mysterious ways.
I’m resigned to having somewhat rattley drawers and will keeping fitting the drawers until they fit.
I wanted to pass on this issue for your comments and for the information of others.

[John TenEyck]

Gotta drawing of the cabinet, and/or some photos? It might help in figuring out why only those drawers are getting pinched.

John

[Andrew Hughes]

Some years ago I made a maple frame and panel door for a fish tank that was too small perfect joinery but wrong size.
I left it out in the weather to see what it would do.. The maple panel pushed all the joints apart but what was surprising was the shape it took. Two opposite corners grew in length even though it was flat sawn. It looked Diamond shaped.
When I make a cabinet I’m carful where I use flat sawn parts and consider rift sawn the best for stability.
Good Luck

[Steve Demuth]

I have no explanation beyond your "wood is organic" but I feel your pain. Some years ago I built a corner hutch from kiln dried Red Oak, acclimated in a wood heated shop space, no less. I put tempered glass shelves in the top of the hutch - loose enough, mind you, that I could fit them into the pentagon shape of the corner easily. Midwinter a year later, and they were so tight in their space that I could not move them. I figure my kiln dried oak had to shrink a minimum of 1/8" over a 16" side to accomplish that. That's equivalent to what you'd expect from a 3% net moisture loss.

That's when I bought my first moisture meter.

[Mel Fulks]

But, was it kiln dried ? Or just air dried ? Some don’t like kiln dried because the color is not as good as air dried.

[Mel Fulks]

Seen a lot of drawers with wood strips on low side . I think they were scared to make the drawers too tight .

[Steve Demuth]

Mel,

This was before I began sawing and drying my own wood, and given where I bought it (at a big sawmill / millwork manufacturer and lumber distributor, I'm certain it was kiln dried. How well, of course, one can wonder. Nowadays, I check moisture on all my wood for furniture projects. Back then I didn't have the tools.

[Mel Fulks]

I have worked in big mills with a lot of stock ,some keep air dried because people ask for it.
Ask them if they are selling some air dried. They will certainly give you an answer.

[Al Weber]

Years ago I built a hunt board chest of curly maple with hard maple drawers. The rock maple was sourced from a mill/kiln operation in central NH. The rock maple had been case hardened and curled into potato chips as I cut it down to size. The drawers are dove tailed front and back with floating bottoms set in groves with room for expansion.
The drawers change length by about 1/8" over their 14" length from high to low humidity periods. Since they are flush fit to the cabinet front they are never flush with the case fronts. I've never understood how there is that much expansion contraction in the drawer dimensions but attribute it to the case hardened maple used. It isn't the3 curly drawer faces as I have measured them to check.
Never went back to that mill.

[Bill Dufour]

40% must be a swamp in your house. where do you live, climate? How many years had the wood dried in the shop climate?
Bill D

[Robert Hayward]

40% must be a swamp in your house. Bill D

Really? Come over to Florida. Where 50% is considered desert dry. The hygrometer hanging on the wall above my desk is showing 53% inside and 69% outside right now. With 80 degrees inside and outside.

[Andrew Hughes]

There’s another wood movement condition to consider. Where the piece is sitting is there direct sunlight on on side during the day is it by a window. Is one side up against the wall and the other seeing air from a cooling system
I know it can make a difference. My wife’s dresser the molding have moved on one side. It’s the side that’s next to a window.

[John TenEyck]

40% is low, Bill, anywhere East of the Mississippi. But you guys make raisins out of grapes out there on the left coast, so I can see how that might seem high.

Back to woodworking, 40% RH is about 7% EMC. That's right in the middle of the target used by many folks who KD wood, including me. But the typical RH is higher than that for most of the year here in the East. KD wood in my storage shed often is 9 - 10% MC. I bring it into my shop and let equilibrate, but it won't come down at all in the summer when the RH in my shop is 50 - 60% (that must seem like a shower to you). In the winter, though my house will go down to 25% in really cold weather if I don't use a humidifier, which I do to keep it at 35 - 40%. If I build in the winter it's going to go up in the summer. Nothing new here, it has been going on as long as people have been using wood to build things. But you have to design and build to accommodate the seasonal changes in dimensions or things can go south. Close fitting drawers are a lesson in wood technology.

John

[Richard Coers]

Thoroughly dry doesn't mean anything. You need to test it with a moisture meter to know how dry it really is. No two boards ever act exactly the same. If I make snug drawers, I only use quarter sawn stock. That stock will not move in width, but instead very slightly in thickness.

[Bill Hays]

Thanks for all the comments. The wood was kiln dried and sold to me by Paxton Hardwood in Kansas City about 40 years ago. It’s been in my various shops since then. I rough cut and mill my material and then sticker it for a couple of weeks. I do the same as I move along if it makes sense. I love the color of aged cherry.
I’ve taken a few more shavings from the offending drawers and the fit is now as good as the rest. I must have left an overlap or missed an overlap when I planed that side. The offending drawers were all sticking in the same area.
Still, I’m surprised the cabinet shrank in volume. I would expect very little change in thickness and can’t quite grasp how a reduction in thickness would cause the entire case to get smaller. It is unique event in my experience. I didn’t finish the inside of the case? Anyway, thanks again for your comments. All’s well that ends well
Bill in Oregon, formerly from Kansas.

[Kevin Jenness]

Are the drawer sides and/or cabinet dividers flatsawn? The issue may be those parts cupping rather than (unlikely imo) the overall opening size shrinking. In any case the primary cause is the difference between shop and in-service conditions. You could conceivably air-condition your shop in summer to minimize that but the truth is in climates like mine there is going to be a significant seasonal swing in relative humidity in use and it has to be designed for. That may mean easing off on the desired piston fit of drawers, using different species or cuts of wood for drawers and related parts or designing your drawers differently. As Mel said you can make NK style drawers with slips for the groove that are wider than the body of the drawer sides (or drawer sides milled thicker at the base) so that a relatively tight fit can be made only at the slips. https://www.finewoodworking.com/forum/nk-drawers

[Lee Schierer]

Thanks for all the comments. The wood was kiln dried and sold to me by Paxton Hardwood in Kansas City about 40 years ago. It’s been in my various shops since then. I rough cut and mill my material and then sticker it for a couple of weeks. I do the same as I move along if it makes sense. I love the color of aged cherry. All’s well that ends well
Bill in Oregon, formerly from Kansas.

Kiln dried wood begins to acclimate to the surrounding environment the minute it leaves the kiln. Unless the moisture level of the environment matches the kiln, the moisture in the wood will change. After 40 years of storage only a moisture check will give you any idea where the wood is.

[Kevin Jenness]

After 40 years of storage only a moisture check will give you any idea where the wood is.

I don't quite agree with that if by "moisture check" you mean using an electronic meter or an oven test. Bill knows that his storage conditions are such as to predict that the wood's mc is somewhere around 10% and the in use conditions will be more like 7% based on average relative humidity. I have a meter but don't pull it out that often because I know from experience what the mc will be based on where my lumber has been stored and for how long. It certainly is true that "kiln dried" in the past doesn't mean lumber is suited for use now.

[Richard Coers]

I don't quite agree with that if by "moisture check" you mean using an electronic meter or an oven test. Bill knows that his storage conditions are such as to predict that the wood's mc is somewhere around 10% and the in use conditions will be more like 7% based on average relative humidity. I have a meter but don't pull it out that often because I know from experience what the mc will be based on where my lumber has been stored and for how long. It certainly is true that "kiln dried" in the past doesn't mean lumber is suited for use now.
Tell me how he knows the wood will be 10% because of his storage conditions. He has a running humidity and temperature recorder in his shop?

[Kevin Jenness]

Tell me how he knows the wood will be 10% because of his storage conditions. He has a running humidity and temperature recorder in his shop?

Bill said in his initial post, "My shop is in the garage where the humidity averages 50 to 60 percent." If that is accurate one would expect mc ranging 9-11%. I have similar conditions in my insulated shop attic storage space. I don't know if or how he monitors conditions, but I do it by occasionally metering lumber when I bring it down into the shop and it is pretty consistent. I'm not against using a moisture meter, I just don't find I need one that often.

[Lee Schierer]

Bill said in his initial post, "My shop is in the garage where the humidity averages 50 to 60 percent." If that is accurate one would expect mc ranging 9-11%. I have similar conditions in my insulated shop attic storage space. I don't know if or how he monitors conditions, but I do it by occasionally metering lumber when I bring it down into the shop and it is pretty consistent. I'm not against using a moisture meter, I just don't find I need one that often.

Obviously something has changed as he is experiencing shrinkage problems. The wood is moving in some direction. Maybe it is just relieving stress due to machining that has been done to make the piece.

[Kevin Jenness]

Obviously something has changed as he is experiencing shrinkage problems. The wood is moving in some direction. Maybe it is just relieving stress due to machining that has been done to make the piece.

Absolutely. If you make closely fitted drawers of lumber acclimated to 50-60% rh and put them in a consistent 40% rh atmosphere you're likely to have problems. You need to get the mc lower before building or fit the drawers more loosely. Simply stress relieving the lumber and acclimating it in a shop with high rh is not going to forestall movement in service.

[Andrew Seemann]

Around here, if a drawer doesn't rattle in the winter, it doesn't open in the summer. We can get desert-like indoor RH in the winter and Florida-like humidity in the summer. You just have to accommodate for it in the design. "Piston fit" drawers are a pipe dream in my climate.