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+-- Thread: Have you ever been defeated by wood movement? (/showthread.php?tid=7373878)
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Have you ever been defeated by wood movement? - FS7 - 09-13-2023
A year and a half ago my neighbors (friends of mine) asked for a dining table in cherry. They didn't want anything fancy - just a simple design, roughly 4' square. I did edge-glued 6/4 panels on top with breadboard ends. The wood was dry (7%) and everything was perfect when it left the house. The humidity in my house is fairly constant for what it's worth. It went literally one mile up the road to their house, where it expanded apparently more than the figure 8 fasteners could take. The breadboard ends are much narrower, and the top is slightly warped on one end (having broken the loose tenon, perhaps). They don't care and have been using it daily, but it bothers me every single time I'm there.
I allowed for something like 3/8" of expansion. I thought cherry was pretty stable. I have done breadboard ends in walnut (just fine, never really moved in NJ) and in sapele here (might move about 1/32" or less over the year). I am still surprised that their house is that much more humid than mine. It's entirely possible they left it wet or something, but I still find it extremely frustrating.
RE: Have you ever been defeated by wood movement? - jteneyck - 09-13-2023
(09-13-2023, 08:27 PM)FS7 Wrote: A year and a half ago my neighbors (friends of mine) asked for a dining table in cherry. They didn't want anything fancy - just a simple design, roughly 4' square. I did edge-glued 6/4 panels on top with breadboard ends. The wood was dry (7%) and everything was perfect when it left the house. The humidity in my house is fairly constant for what it's worth. It went literally one mile up the road to their house, where it expanded apparently more than the figure 8 fasteners could take. The breadboard ends are much narrower, and the top is slightly warped on one end (having broken the loose tenon, perhaps). They don't care and have been using it daily, but it bothers me every single time I'm there.
I allowed for something like 3/8" of expansion. I thought cherry was pretty stable. I have done breadboard ends in walnut (just fine, never really moved in NJ) and in sapele here (might move about 1/32" or less over the year). I am still surprised that their house is that much more humid than mine. It's entirely possible they left it wet or something, but I still find it extremely frustrating.
Check the Shrinkulator. 7 to 12% moisture content change on cherry would give a dimensional change of 0.33" for QS grain for a 48" wide top, and 0.64" for plain sawn. If you used plain sawn and the RH in the customers house is consistently high (no AC), then that could explain it.
John
RE: Have you ever been defeated by wood movement? - Willyou - 09-13-2023
You don't say how much it expanded, but if the figure 8s are not oriented at an angle (ideally 90 degrees) to the direction of movement (parallel with the grain), they can't allow for the movement. It may be too late to do anything, but it might be worth a try to replace them with "Z" clips. Or, you might try removing the figure 8s from the sides of the table that don't have the breadboard ends. Those are the two sides where the 8s are most likely perpendicular to the grain.
RE: Have you ever been defeated by wood movement? - FS7 - 09-13-2023
They have AC. It's older than my house by probably 40 years. But new enough to have central air. They have a wood stove in the adjacent room, and in the winter that room is often 85+ and dry as a bone. I expected shrinkage, but not expansion (ar least not significantly).
And yes, I did orient the fasteners at an angle. I did test the rotation and they worked fine.
It would probably not be all that hard to fix, but they don't care. At present they have a mismatch between the breadboard and the panel along with maybe a 1/32" warp in the panel on one corner. Enough to bother me, but not enough to bother them.
RE: Have you ever been defeated by wood movement? - Woodenfish - 09-13-2023
I have always avoided breadboard ends completely just because of these stories, I sleep good at night.
RE: Have you ever been defeated by wood movement? - AHill - 09-14-2023
I wouldn't say defeated, but definitely frustrated. I built a very nice tool cabinet when i lived in the high desert north of LA in California. I moved to St. Louis, and every single drawer was stuck. The wood had expanded due to the higher RH. I had to remove the back panel and use a soft mallet to remove the drawers. I ended up planing the sides to gain more clearance, and then waxed them for extra measure.
RE: Have you ever been defeated by wood movement? - EightFingers - 09-14-2023
Moving from Kansas City to Hawaii. ALL my drawers got tight. I spent a week getting them all squared away.
Now, I’m in Las Vegas.
Yep.
My drawers are loose.
RE: Have you ever been defeated by wood movement? - MauleSkinner - 09-14-2023
It took me a few years to get my wooden vise screws working smoothly.
RE: Have you ever been defeated by wood movement? - jteneyck - 09-14-2023
(09-13-2023, 09:16 PM)FS7 Wrote: They have AC. It's older than my house by probably 40 years. But new enough to have central air. They have a wood stove in the adjacent room, and in the winter that room is often 85+ and dry as a bone. I expected shrinkage, but not expansion (ar least not significantly).
And yes, I did orient the fasteners at an angle. I did test the rotation and they worked fine.
It would probably not be all that hard to fix, but they don't care. At present they have a mismatch between the breadboard and the panel along with maybe a 1/32" warp in the panel on one corner. Enough to bother me, but not enough to bother them.
If you built the breadboard ends the same width as the field you were in for disappointment from the beginning, because anytime the moisture content changes the field will either be wider or narrower. Narrower is OK, but wider will expose the end grain of the field, not pretty. So I always make the ends wider than the maximum width I expect for the field at the highest moisture content I expect it will experience.
In any case, you have to plan for the outboard mortises to be wider on both sides of the tenon to account for the maximum expansion/contraction you expect the field will see. That will prevent the field from buckling or splitting. Of course, the way the top is attached to the base must allow for that same amount of expansion.
The mismatch you now see in the width of the panel compared to the breadboard end is to be expected. And 1/32" warp is pretty much nothing. It's solid wood, and wood moves. If you want to make a breadboard end tabletop that looks perfect year-round, you need to use veneered plywood/MDF for the field.
John
RE: Have you ever been defeated by wood movement? - KC - 09-15-2023
(09-14-2023, 07:27 PM)jteneyck Wrote: ... If you want to make a breadboard end tabletop that looks perfect year-round, you need to use veneered plywood/MDF for the field.
John
I've never like the look of a proper (functional) breadboard end... and when I was building things for money I wouldn't use them. **
Too many people don't understand the 'why', and my feeling was (is) they sure wouldn't like it when things started moving around.
** But used solid breadboard 'caps' on the ends of many, many mesquite tables. Working mesquite can spoil a fella.
