1/2" red oak panels curling when edge jointed after resawing

[footprintsinconc]

hello everyone!

my friend's current kitchen cabinet doors are flat panels (the flat panels being 1/4" oak ply). he went and purchased 5/4 red oak and resawed it and finished it so that he had a total thickness of 1/2". the then jointed the boards on edge so that he could make panels out of them and routed the perimeter to give it a designed look and was going to install them onto the flat panels to give the cabinet doors a raised panel look. however, almost a day after jointing the boards on edge and routing a pattern around the perimeter, the panels started to curl up. they are about 15" x type cabinet height and are curling up on the sides by about 1". he doesnt remember which is the resawed surface anymore since he surfaced all side of the board, however, doesnt remember the wood being wet either after resawing. a finish had not been applied to the doors yet. what do you think is wrong?

[ragswl4]

I don't think there is anything wrong per se. I had a similar experience with another type of wood (Lyptus). Sometimes even though the wood appears dry, it may not be totally dry in the center. When resawn this new exposed surface now starts to dry and of course it shrinks and will draw the edges upward. The wood in the center of the board is also under more stress that the wood on the outer edges, so when resawn this stress is released and adds to this problem.

[HarmsWay]

I'd go with RAG's second theory - internal stresses. You say he jointed the edges and resurfaced the faces? I assume resurfaced means ran through the planer (as opposed to jointing the faces). Are you saying each door has 1" of cupping?

Bob

[Black wallnut]

As Rags said seems somewhat normal and not completely out of the ordinary for wood to move after milling. Good reason to assemble doors right after milling the wood. Lots of things can cause wood movement after milling.

[Anna]

As Rags said seems somewhat normal and not completely out of the ordinary for wood to move after milling. Good reason to assemble doors right after milling the wood. Lots of things can cause wood movement after milling.

Doesn't it make more sense to rough cut, then let the wood acclimate for several days before final milling? If the panel starts to warp when it's already installed in the door, doesn't that create even more stresses on the structure?

Just wondering.

[Ken Massingale]

Doesn't it make more sense to rough cut, then let the wood acclimate for several days before final milling? If the panel starts to warp when it's already installed in the door, doesn't that create even more stresses on the structure?

Just wondering.

Absolutely. if the wood is going to move it doesn't matter if it's assembled. the guys RO probably wasn't 'wet, but had different MC in the middle than outside. When resawn the pieces should be stickered and stacked with significant weight on top for a few days This is one rule I have learned the hard way. I've checked it with a moisture meter and had the same readings, the blasted stuff still warped or turned up on the sides.

[ragswl4]

I have noticed a similar problem with the wood I am currently working with but not during resaw. When making door frames I was jointing the face and edge of a 6 1/2" wide board, then ripping the other edge and finally running it through the planer to flatten the other face. I would get a flat board with two 90 degree edges. I would then rip the board into three 2" wide boards for the door frames. About 50% of the time I would notice that the 2" wide boards were no longer flat and had to be jointed and planed again on the faces. I think its the same kind of stress being released in the wood when it is ripped.

I now rip to final width before I face joint and plane.

[footprintsinconc]

thank you for your replies. i will pass on this information. i think its the stress release as you all have said and they should probably be stickered and stacked as ken suggest with weights. but doing this means that it adds days to your project where you are doing nothing but waiting (i guess you can work on other aspects of the project in the mean time).

here is a question: when the wood is resawed at the mill into lets say 12/4, 3/4, 4/4 etc, i guess they dont have this problem because all the wood gets stickered, bundled and tied (hence the self weight)?

rags, that is an interesting suggestion about ripping them before face jointing and planing. i myself have face jointed and planed before i cut them to their proper widths. i wonder how many people do that and have noticed this as you mention?

[Ken Massingale]

thank you for your replies. i will pass on this information. i think its the stress release as you all have said and they should probably be stickered and stacked as ken suggest with weights. but doing this means that it adds days to your project where you are doing nothing but waiting (i guess you can work on other aspects of the project in the mean time).

here is a question: when the wood is resawed at the mill into lets say 12/4, 3/4, 4/4 etc, i guess they dont have this problem because all the wood gets stickered, bundled and tied (hence the self weight)?

rags, that is an interesting suggestion about ripping them before face jointing and planing. i myself have face jointed and planed before i cut them to their proper widths. i wonder how many people do that and have noticed this as you mention?

Hey Omar,
Just based on what I've seen and experienced both internal stress and moisture differences do have effects. Internal stress usually distorts the wood as twist/warp, while moisture differences will cause cupping. Seems like we could say stress works on the length profile and MC on the width. I'm sure that is not all inclusive but I'll throw it into the pile of possibilities anyway. I've had nice dry, perfectly flat and straight Maple boards twist and convolute so badly when being ripped I had to stop the TS midstream to keep from getting hurt. They say trees cut from a hillside can do this, this sucker must have been growing on a wall of the Grand Canyon.

As for the wood at the mill, I see alot of the stuff on the top of the stacks cupped and twisted. I reckon like you said the top boards keep those under them from distorting.

[jackellis]

This happened to me with 6/4 Ash when I tried to resaw it. Just about drove me over the edge.

[footprintsinconc]

jackellis, out of curiosity, what did you do then?

[Jeffrey Schronce]

This is a 15" wide solid red oak board? Milled to 1/2"?

Odd to see ash and red oak behaving like that.

[footprintsinconc]

the widest was 15, but some narrower upto 12" of 1/2" red oak.

[Jeffrey Schronce]

the widest was 15, but some narrower upto 12" of 1/2" red oak.

I believe that issue was moisture content. 15" wide 5/4 red oak is a pretty decent slab and isn't the easiest to properly dry. My guess is that the core moisture content was likely 10-14% and when the freshly exposed wood started drying it went every which way!

Thick oak can move quite a bit upon cutting. Yesterday Thom was supervising my construction of a mobile base. The oak was 2" thick prior to planning down to 1 5/8 (see Thom I am admitting is was thicker that 1.5" . . lol) so lots of freshly exposed wood. I know the moisture content was under 10% on this stuff, likely a couple points less. Anyway, when cutting it the stuff pinched the back of the outfeed so hard I could barely push it through and we are talking Unisaw with fresh blade! Unreal how much that wood moved and we are talking 1.5" stuff here!

IMHO you should expect problems from a 15" wide solid board which has been resawn from 5/4 to 1/2" stock. Results would have likely been much better with a glue up of (2) 7.5" wide boards. Of course you would have a glue line and grain issues to deal with. Dont get me wrong I know where you are coming from using a solid panel for appearance purposes, just plane to have to work with it.

Wonder if the current wood could be moistened and flattened in a veneer press or similar?

[footprintsinconc]

sorry jeffery for the misunderstanding. the 15 wide or 12" wide boards are made up of two or three boards glued togather. the stock was 5/4 varied widths and then were resawn individually, surfaced and put through a thickness planer to get 1/2" stocks. then they were glued togather and then the boards were cut to width. then a pattern was routed into the edge of the boards and were set to be finsihsed. this was done all in one day. when my friend noticed that they had started to cup. they cupped upto 1" in one day after rasawn.