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I made a several raised panels. Used a planer sled to flatten them and finished on drum sander and sanded down to 240. They weren't dead flat but I'd say the worst was no more than 1/32" off when checking on flat surface. I applied Arm-R-Seal and let them dry outside. It's a little warm for the season but not hot. Like high 70's. When I check on them later in the day they had all cupped. Some a little some alot. The worst was now close to 1/8" off. Could this have been caused by the heat? The panels were a warm when I picked them up.
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one side finished only?
the major cause of cupping right after improperly dried lumber
Let us not seek the Republican Answer , or the Democratic answer. Let us not seek to fix the blame for the past. Let us accept our own responsibility for the future John F. Kennedy
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They are likely to flatten back out again on their own when the MC equilibrates. Bring them back in and wait a day or two.
It's best not to move wood from one place to another when building/finishing something.
John
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Joe both sides were finished. I got the boards from 2 different lumber yards. Some were regular KD and the rest were from a recycled barn that were S2S
John I usually apply finish and let pieces dry in the garage but there were alot many pieces this time and figured it was faster and easier to do it outside.
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Quote:Some were regular KD and the rest were from a recycled barn that were S2S
can you tell the difference?
I suspect the barnwood was air dried and even old it would not act the same as the KD stock.
Let us not seek the Republican Answer , or the Democratic answer. Let us not seek to fix the blame for the past. Let us accept our own responsibility for the future John F. Kennedy
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03-14-2017, 11:22 AM
(This post was last modified: 03-14-2017, 11:23 AM by joe1086.)
Were any of them sitting exposed to direct sunlight?
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My guess is that the sun baked the top and if the cupping formed a shallow bowl then I could be right. As suggested give them a day or two indoors with air flow all around and it is likely the problem fixes itself.
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(03-14-2017, 11:07 AM)Juss1 Wrote: Joe both sides were finished. I got the boards from 2 different lumber yards. Some were regular KD and the rest were from a recycled barn that were S2S
(03-14-2017, 11:20 AM)JGrout Wrote: can you tell the difference?
I suspect the barnwood was air dried and even old it would not act the same as the KD stock.
I suspect that both, if they had been in the shop for a week or two, were at the same equilibrium. Makes no difference if they were KD or AD originally. Now they're BOTH air dry.
https://www.fpl.fs.fed.us/documnts/fplgt...3/ch03.pdf
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Well I disagree with your conclusion.
I have treated both differently for good reason, I have experienced similar conditions when mixing AD and KD.
Let us not seek the Republican Answer , or the Democratic answer. Let us not seek to fix the blame for the past. Let us accept our own responsibility for the future John F. Kennedy
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Yes. They were in direct sunlight for several hours. I can't work on them till this weekend so I'll try and let them be and hope it flattens out a bit.
Joe I don't remember exactly which ones were AD and which were KD.
