Issue with white oak glue ups

[Rick Herrick]

My forays into using more hardwood vs plywood has done me in once again.  I am using hardwood panels for two dresser side panels (~ 27" x 12") and 6 drawer front panels.  I did the side panel glue up a week ago and then planed them to 1/2" final thickness.  Still haven't worked out other issues so I put them on a shelf.  Just noticed today that have warped/cupped.  One more than the other.  Is this fixable ?

1. Did my glue up go bad and I didn't notice
2. Did I plane them down too soon after the glue up
3. Did I let them sit too long before doing something with them

Kind of worried they are no longer usable as is.

 

[ultane]

The wood is alive. Once you plane it, multiple forces have to come to equilibrium again, and the wood will seek out a new stress free state. (Or so someone once said on the internet)

 

[smorgasbord]

Welcome to the world of wood movement. It's hard to say exactly what caused your problem, but in general there are two likely causes:
1) The moisture content in the boards changed as they sat on the shelf in your shop, and so the wood expanded/contracted at different rates based on the grain directions.
2) When you planed the boards down you relieved some internal stresses that then caused the boards to warp from their prior state.

From your description, it sounds like #1 is more likely. What is the humidity in your shop, and how is it changing? How long did you have the boards in the shop before you glued them together? What will the humidity in the house where the dresser is going?

Hard to tell, but it looks like you have what's called "Plain sawn" boards. Looking at the end grain, it means the grain run mostly parallel to the face of the boards. This can be very pretty, but since the grain isn't perfectly straight, as the boards take on or lose moisture, the grain will either cup more or straighten. Quartersawn boards, where the grain runs from one face across to the other face, tend to be more stable with regards to moisture changes.

One thing some people do is orient the grain on wide glue-ups such that each board's grain "cups" in the opposite direction of the board next to it. This will mean that any cupping is localized and therefore reduced across the entire width.

In general, you need to know the moisture content of the wood before you cut it, as well as the humidity levels in your shop. Ideally, your shop's humidity would be the same as the final destination of the piece, but that's not always achievable, at least cheaply. A moisture meter would be worth investing in, too.

If the boards aren't final width, you can recut them and then re-glue them up. Put battens across both faces of the boards and clamp those together to help hold the boards flat. Don't remove the battens until you're ready to plane and trim to size AND insert into the frame. If you're lucky, the frame may help hold the boards flat, but ½" thick oak may actually twist the frames if they're not secured to each other as a carcase.

 

[sherbert409]

How long did you have the lumber before you started milling it? Normally I will put the lumber in my garage and wait a week before I joint one face and one edge. I will try (but not always) wait a week before planing to the final thickness and ripping to the final width. After this you get an idea of how this stock will behave with milling. At this point you could re-joint before planing and ripping.
The thicker the sock the more issues you are likely to encounter, because it takes longer to dry and more internal stress could be at play. If I resaw anything I don’t even touch it with the jointer or the planer for at least a week after resawing if I think it will move on me.

The waiting is the hardest part.
-Tom Petty

Sent from my iPhone using Tapatalk

 

[mrFinpgh]

My forays into using more hardwood vs plywood has done me in once again.  I am using hardwood panels for two dresser side panels (~ 27" x 12") and 6 drawer front panels.  I did the side panel glue up a week ago and then planed them to 1/2" final thickness.  Still haven't worked out other issues so I put them on a shelf.  Just noticed today that have warped/cupped.  One more than the other.  Is this fixable ?

1. Did my glue up go bad and I didn't notice
2. Did I plane them down too soon after the glue up
3. Did I let them sit too long before doing something with them

Kind of worried they are no longer usable as is.

It's hard to say without more information about your workflow.

In general - wood moves because of tension, moisture, and expansion/contraction. In general, with flatsawn wood, wood cups away from the heart side.

If the wood is expanding more on one side than the other, this kind of cupping is a likely outcome.  I'm guessing that this is what happened here.  Maybe one of these applies?

1. A significant amount of material was taken off one face, only a very small amount taken off the other (or none).  This could cause an uneven expansion/contraction of the material and lead to cupping.
2. After planing, the panels were placed flat on a surface and air didn't flow evenly across both faces.  This could also lead to moisture being absorbed more on one face than the other.  If one was stacked below the other one, it might have had less uneven absorption as the top panel have functioned like a buffer.
3. In theory, it's best to do a rough milling to within 1/8" of final dimensions, let the material rest on stickers for a day or even a week, and then do a final milling to get it to the finished thickness/width.

One thing I've done that seems to work well is to place any panels in a thick contractors bag and remove as much air from it as possible before closing the bag.  That essentially minimizes outside moisture from getting to the panel and seems to keep them flat.  However, now you pull the panel out and it is potentially exposed to new ambient humidity than where it started off, so it's best to do that only when you're sure you're going to be able to either apply a finish soon after or if your going to attach it to something.

 

[Steve1]

I am not sure, but off a couple of suggestions.

1) Don't plane off much material at one time.  It can move after planing.  I let the wood acclimate in my shop, then skim the two sides, then put them away for a while (at least a few days, ideally) then check if they are still straight and skim again.  Might have to go through this several times if taking off a lot from the thickness.

2) When you lay out the boards for gluing, mark the edges as shown below.  Then do a final cut on the edge, with jointer or table saw with the "in" face of the board against the fence, and the "out" face away from the fence.  If your blade is not perfectly square, it will level out the error.

 

[chrisrosenb]

The moisture content of the wood is to high. Flip the piece over with the bow up & it will flatten back out. Once it flattens out, store it so air can flow over both surfaces.

 

[ChuckM]

Rick,

The cup is fixable, but you didn't say what the panels are for. As a door, may be yes, may be no. Something else that is glued or screwed to a case, likely yes.

Here's how. Place the board as shown in your photo (cup side up). Steam the cup side (iron and wet cloth placed on the board) until the board is flattened.

If the board cups again, do the steam flattening just before the final assembly. Google some to see how the steaming is done.

If you aren't doing that, remember to plane both sides of the board alternately so you are removing equal amt of material from each side. Acclimatization as others have pointed is the key. If something still warps after you take care of all the precautions, it's just a bad apple.

 

[Cheese]

Rick, I always try to plane the same amount of material from both sides of the board. Sometimes it's difficult because of blemishes, grain, knots and such but I try.

And it's not just wood that has these issues, years ago I found out that if I took a 3/8" cut off of one side of a 2" thick block of Teflon and a 1/8" clean-up cut off of the other side, the Teflon would potato chip on me within 24-48 hours.

As others have noted I also glue up boards with alternating grain patterns, that helps keep things straight.

 

[bertv]

First try this: put the panels back on the shelf — BUT upside down (as compared to the first time). Leave them for a while, check once in a while. If there is no movement towards flat, you try any of the other suggestions here.

 

[Birdhunter]

Those cupped boards look all too familiar. I've encountered the same problem often and it is always with plain sawn boards as someone above mentioned. If I can't get quarter sawn boards, I'll joint/plane the boards with a lot of extra wood left. I'll let them sit for a week and them joint/plane them again. Usually 3 cycles eliminates the cupping and I then trim them down to final size and hope that stay flat when I apply the finish. I try to avoid water based finishes with plane sawn wood as the moisture can trigger cupping.

I've made a number of furniture pieces with quarter sawn white oak and it is both beautiful and easy to work.

 

[RJNeal]

As Bert said, try flipping them for a bit.
This reminds me when I delivered 3 end grain cutting board that were dead flat to a retailer.
I placed them on their granite countertop at their POS in a stack. Two days later they call me up the tell me that the boards were warped. I went it to pick them check them out and pick them up. They were still in the same place. The top board had warped a little more than the middle board. The botto one was fine. Then I looked up th the ceiling and there was one of those big heaters forcing warm air down on them. So the tops dried out and the bottoms were sealed off with next board down or the countertop.
I exchange the boards took the warped boards back to the shop and placed them in my vertical storage rack. A month or so later they were flat again.

 

[ChuckM]

This door (poplar) was steam fixed before it was installed, and it has stayed flat luckily since 2014, the year the cabinet was built for the shop. My shop's humidity swings from 30% (?) (summer) to 70% (winter). The cabinet was completed in early fall, and the door gap (reveal) changes among seasons.

Edit: The current reveal at 57% (8.8* C) is shown in the second image.

 

[Rick Herrick]

I can't tell you guys how grateful I am for all this good info.  It does prompt about 20 more questions but I'll refrain until I do some more work.

I assumed these panels are no longer usable so I brought them into the house, did some stickering and then put some weights on them (high spots are facing up), just as an experiment.  As mentioned by a couple of you, I might be able to salvage them but worry about them failing again later.  But I'll see how it goes.  I do need to work on a 'cookbook' for how I do this in the future, using some of these tips.  In my work life I have much better success when I make lists and improve them as I go, thinking things through better.

The two panels in question are to be 12 x 27 and will be center panels for dresser side panels.  They are 1/2" thick with a 1/4" x 1/2" tongue, all around to fit into the rails/stiles.

I basically know about humidity, stickering and grain but I know just enough to know I don't really know much.  Right now I think my main errors so far have been,

1. Glued up the panels prior to planing and I think I should plane first (little at a time) and let them acclimate a good bit.

2. Taking off way too much in one session.  My supplier did a terrible job initially taking the 4/4 to 13/16" so I tried to clean them up as best as I could and then I glued them up.  I went from the 13/16 to 1/2 in one go.

3. Just put them back on a shelf with no space, stickers or anything.  I should have known better on this one.  I have had better success with 3/4" and thicker stock for some table and dresser tops but going to 1/2" probably requires a little more patience.

I really don't know how to address humidity.  Just put my head in the sand on this issue up until now.

I do intend to go looking for quartersawn going forward.  I do like white oak and want to keep using it. 

Appreciate all the help.

 

[Rick Herrick]

My shop's humidity swings from 30% (?) (summer) to 70% (winter). The cabinet was completed in early fall, and the door gap (reveal) changes among seasons.

Thanks Chuck, what type of meter or gauge do you use?  Regarding wetness, the author of the plans I am following has a moisture meter but it is a > $400 item,,, ouch.

 

[rvieceli]

[member=72312]Rick Herrick[/member] consider investing a good moisture meter.

Trust but verify. you really don’t what you are starting with without measuring it yourself.

I use and really like this one from Wagner. It’s a pinless one that works well.
https://www.tools4flooring.com/wagner-orion-910-deep-depth-pinless-wood-moisture-meter.html

These folks usually have the best pricing and are good to deal with.

If you don’t already, consider sticking a dehumidifier in your shop and run it year round. It helps. I hook up a hose to the thing and run under the garage door.

Ron

 

[ChuckM]

Rick,

I build mostly with rough lumber that is not quarter sawn. I use these tools to do my calculations and measurements:
https://www.leevalley.com/en-ca/sho...6281-lee-valley-wood-movement-reference-guide (but you should be able to find free online calculators)
https://www.leevalley.com/en-ca/sho.../moisture-meters/71986-digital-moisture-meter

(price in Cdn dollar)

Edit: I also need this chart to find my EMC (in Canada, Table 3): PDF download linkhttps://www.google.com/url?sa=t&rct...odFPL268.pdf&usg=AOvVaw3ga-maDfpXWx35m20PJrbM

Procrastination sometimes is a virtue  [big grin] like this oak lumber that had sat in the shop for over 10 years before I finally used it last year for a chair project.

 

[Steve1]

Then, today, I learned still one more way to bend a glue-up.

Maple desk top.  Sprayed a few coats of waterborne urethane clear topcoat on the bottom, then turned it over to spray the top.  The plan was 4 coats on the top surface, but it was seven coats before my last coat was nice.  Next morning its looks like OP's board.  I guess the maple didn't like all that water on one surface.

I was planning on letting it cure a little while longer before touching it, but I carefully bolted it onto the desk structure, with a little reverse bend, and will let it like that for a while.

 

[Michael Kellough]

Didn’t read all the posts so don’t know if this was mentioned but a common problem people do when starting out work with natural wood is after jointing one side they plane the opposite side all the way down to the final depth. Instead, you need to take an equal amount off both sides to reduce the chances of cupping/warping. If there was tension the wood it will still move but you do what is best and cross your fingers.

The risk is lessened if you start with acclimated wood and lessen more if it’s quarter sawn.

Quarter sawn white oak is one of my favorite woods. But I used rift sawn on this sculpture project because it’s less flashy.

 

[mcooley]

All good points above.

I work with White Oak quite a bit for client furniture projects.

My workflow might help:

Shop is kept close to a constant rate of humidity which is a little drier in the winter than the summer but between 45-35 RT.

I let all boards acclimate for a week or more.

I try to buy boards close to the thickness I will use them at.

Minimal planing from both sides usually and then square the boards. I always leave more material than I need in both width and thickness until I am certain they aren't moving.

I only use Quartersawn White Oak both for stability and looks (I prefer the look over flatsawn).

I would never do a table top even of modest size at 1/2 thickness without some kind of breadboard or similar which allows the wood to move.

If using flatsawn material then breadboards are used again but also if possible (without ruining the look) flip the direction of the grain of the boards so no two are matching side to side. This can help but is not absolute.

Know that the wood is coming from a reputable source and has been properly dried.

With all this said, some movement may still occur and I take those high spots off by planing and/or sanding.

*In your photos the 1/2 thickness flatsawn is going to be a hard thing to control and at the widths you have the two boards with the grain running in the same direction are most likely going to move. At that thickness you don't really have material you can afford to lose so unless they relax over time you might be better off cutting then gluing again but with the needed adjustments.

*And airflow is always required so never leave stacked tight.