# Please help with my warping pine table top



## TazloverMom (Feb 13, 2021)

My son made me a beautiful farmhouse dining table - his very first furniture project. It is all of pine boards.





















The finished project was brought to my house about a month ago. The base is painted. The top is not yet attached to the base, as the top not stained- as I was sampling colors. The problem- the table top is warping. Is there anything I can do to stop the warping? Reverse the bowing that has happened? Also, because of this issue, if we can "fix" the problem, how would you recommend we attach the top to the base? Thanks!


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## John Smith_inFL (Jul 4, 2018)

ohhhh noooooo that has got to be heart wrenching !!!
please tell us what part of the world you are in, and where the table was made and where it was moved to in your home.


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## Geeze (Jan 28, 2021)

Nice looking table! I would screw some temporary cross pieces [3-4] between the leg supports. The issue will be a suitable material. If you can find some gently warped 2x4's you can arrange those with the warp down to pull the warped up top level. The brute force method would 3-4 pieces of [3/4" or 1"] angle iron. I've even made 'L' Brackets out of wood but they may need to on the big side to counteract the warp. The advantage of the angle iron [or aluminum] would to have the down 'L' snugged up to the leg support and attach screws horizontally. Whatever you use I would not remove.

Once you get the top level I'd recommend finalizing the color and paint both sides. There are wood sealers / treatments that you can paint over as an option.

Let us know how it ended up.

Russ


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## TazloverMom (Feb 13, 2021)

John - We are in Central NY area. My son built it in his garage, which he has a space heater in and moved it to my home.

Russ - thanks. My son will be following this thread (and may chime in). You mention painting the top - would I be able to stain it as originally planned? Instead of painting?

Thank you


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## Geeze (Jan 28, 2021)

You'll need to seal it somehow to keep the wood from absorbing or losing moisture. Were you planning on putting a finish on top of the stain?

I recommend Flexner's 'Understanding Wood Finishing' as he cover just about everything in this area.

Russ


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## TazloverMom (Feb 13, 2021)

I was wanting to stain it, to "match" the color of the seat of the chairs. I had read a little on staining it - so was planning on conditioning the wood, staining and sealing.


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## woodnthings (Jan 24, 2009)

There's a slight difference in terms, warping being used for the overall condition of a board, from wikipedia:








Wood warping - Wikipedia







en.wikipedia.org











What's happening is the top planks are drying out and "cupping". If you place a short straight edge over each separate plank you see that it's rounded in shape. This naturally occurs when "construction grade" lumber from the box stores are brought into a dry house during the winter months when the humdity is very low. Also there are several boards whose end grain is in the shape of a saucer. These are the worst offenders! The one board I see with an "eye ball" is least likely to cup because the end grain shows mostly vertical grain. Vertical end grain is the least likely to cup.
Since the top is NOT fastened to the frame, fastening methods are not an issue in this case.
So you have two separate issue that are contributing to the "warping".
How to fix it?
I would let your son take the top back to reconstruct it with more vertical grain boards. It would be much better in the long run than trying to salvage what's there. He needs to join this forum and he will learn a lot about wood movement and construction method and especially about using "construction grade" lumber from box stores.
How to join boards edge to edge is another topic often discussed here when table tops are being made and when they start to warp.
It's my opinion that the top you have would need a whole lot of work, which would include replacing the worst offending boards. It may just be easier to saw it apart down the glue joints AND possible right through the centers of the worst boards to minimize the cup. That's what I would do if buying new boards is out of the question. By ripping them down the length, the amount of cup is divided in half and the stresses inside the board are greatly relieved. Then it's a matter of using the proper Joinery" methods having the straightest edges possible to mate together. Some woodworkers alternate the grain direction by flipping some boards end for end making them equally stressed.





His other videos:


https://www.youtube.com/channel/UC_mcFH_r7Aq6SyQ0HrGaenQ


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## Rebelwork (Jan 15, 2012)

There are several problems but two are the obvious.

#1... the boards ae too wide. Would have been better with 2×2 or 2x4.. I think some companies off per 2x3's.
#2....the boards need to be alternated as the photo shows.


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## Rebelwork (Jan 15, 2012)

I remember when microwaves first came out. I use to make carts for them to sit on . All 2×2 construction. Made many till it took off and now have them in the kitchen cabinets. Boy wax pine cheap then...


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## Jar944_2 (Oct 30, 2020)

Rebelwork said:


> There are several problems but two are the obvious.
> 
> #1... the boards ae too wide. Would have been better with 2×2 or 2x4.. I think some companies off per 2x3's.
> #2....the boards need to be alternated as the photo shows.
> View attachment 424033


So ill disagree on both #1 and #2 (sort of)

Boards properly dried and at a equilibrium moisture content will not move significantly. Yes there is more opportunity for movement in a wider board, but that doesn't mean it will. I have a gate leg table that has single board drop leaves that are roughly 24" wide and flat sawn. No cup, and nothing restricting it from moving. 

Alternating growth rings just makes a panel or table top more likely to cup in alternate directions if there is movement. I prefer all one direction if possible, but grain / face selection takes priority over orientation. If it cups I would rather have one large cup across the entire top. Simple stretchers underneath will prevent the movement.

None of that really applies to construction lumber since it's usually case hardened from the rapid kiln drying process and still relatively wet inside the board. The case hardening means that regardless of how long it sits there it will move when processed.


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## Steve Neul (Sep 2, 2011)

Sometimes you just get a bad board. I believe the majority of your problem is with the board in the very center. I think if you cut that board out of it and replace it you won't have much trouble with the top anymore. Once you screw it to the base it should eliminate any further problems however be sure to elongate the screw holes because the top will shrink in width over time and it needs to be allowed that movement. Then when you do finish the top be sure to finish both sides. A cup warp normally happens when there is a difference in moisture content from one side to the other and if you just finish one side it will allow moisture from the air to get to the underside.


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## Kerrys (May 2, 2016)

Steve is correct, one board in particular seems to be causing a lot of the issue but there also appears to be an issue with the glue up. One joint is failing significantly and looking closely at a couple of the other joints they appear to be failing or soon will. Just guessing but it looks like glue coverage was not very good and I am curious as to what glue was used. I also question how it was clamped.


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## Rebelwork (Jan 15, 2012)

Jar944_2 said:


> So ill disagree on both #1 and #2 (sort of)
> 
> Boards properly dried and at a equilibrium moisture content will not move significantly. Yes there is more opportunity for movement in a wider board, but that doesn't mean it will. I have a gate leg table that has single board drop leaves that are roughly 24" wide and flat sawn. No cup, and nothing restricting it from moving.
> 
> ...


You don't have to agree. A proven fact in the furniture company.. 10 million a year in sales making restaurant tables you learn from past mistakes.we won't go over 4" on a board...we alternate..

Remember Jacobe furniture is #1 in the country producing butcher block restaurant tables ib the U.S. producing 400 a week.. Notice the stacks of butcher blocks laying around.

We have 60 hydrolic clamps I believe and a glue machine. The boards are sized 4" over size in length, glued and clamped, left in the clamps 24hrs using TB2. After they come out they are stacked and allowed to stand for 24 more hours. Then it's off to the planer/sander then they make there way to the hand sanders and finish


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## Rebelwork (Jan 15, 2012)

Why we have two SCM sanders. The first one is a planer/sander. The second is backup or if a top gets sent back. Cross sander marks are are biggest problem. Every once in awhile one gets though...

Let's see we did 400 a week x 52 weeks x7 years I was there. Hum..
notice the circle in black...


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## TazloverMom (Feb 13, 2021)

Jar944_2 said:


> So ill disagree on both #1 and #2 (sort of)
> 
> Boards properly dried and at a equilibrium moisture content will not move significantly. Yes there is more opportunity for movement in a wider board, but that doesn't mean it will. I have a gate leg table that has single board drop leaves that are roughly 24" wide and flat sawn. No cup, and nothing restricting it from moving.
> 
> ...


Thank you. What you'd you recommend to try and correct it?


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## TazloverMom (Feb 13, 2021)

Kerrys said:


> Steve is correct, one board in particular seems to be causing a lot of the issue but there also appears to be an issue with the glue up. One joint is failing significantly and looking closely at a couple of the other joints they appear to be failing or soon will. Just guessing but it looks like glue coverage was not very good and I am curious as to what glue was used. I also question how it was clamped.


My son is following - not sure if he saw your comment / question. But I will ask and see. Thank you


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## Jar944_2 (Oct 30, 2020)

Rebelwork said:


> You don't have to agree. A proven fact in the furniture company.. 10 million a year in sales making restaurant tables you learn from past mistakes.we won't go over 4" on a board...we alternate..
> 
> Remember Jacobe furniture is #1 in the country producing butcher block restaurant tables ib the U.S. producing 400 a week.. Notice the stacks of butcher blocks laying around.
> 
> ...


Commercial table tops bolted to a 8" square pedestal without the support of an apron or stretcher dont have much in common with most dining tables


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## Jar944_2 (Oct 30, 2020)

TazloverMom said:


> Thank you. What you'd you recommend to try and correct it?


Cut it apart at the glue lines, re-joint the edges and re-flatten the faces then glue it back together.

Since there is no finish applied yet it should be relatively easy to rebuild.

Once its rebuilt keep a few stretchers clamped to the top to keep it from warping again until it can be fastened to the bases.


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## Rebelwork (Jan 15, 2012)

Jar944_2 said:


> Commercial table tops bolted to a 8" square pedestal without the support of an apron or stretcher dont have much in common with most dining tables


We don't just make commercial tops. We make apron tops as well.
But here is a table exactly to the one mentioned..
The companies profile is the largest manufacture of butcher block tops, my job there was to make high end customer furniture.

I have plenty to do with custom tables, etc.


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## Rebelwork (Jan 15, 2012)

Not all table require aprons


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## DrRobert (Apr 27, 2015)

First of all, he shouldn’t feel bad, this has happened to every one of us at some point in our ww’ing experience. I‘m sure you’re quickly realizing there are lots of opinions, mostly because there are usually several different ways to do things.

In a nutshell, cupping, etc occur due to unequal drying, internal stresses in the wood, and the saw cut of the lumber. By this I mean quarter sawn, rift sawn, flat sawn, the tendency to cup increasing. The board on the left is quarter sawn, the next one is mostly rift and the next flat.

Building a project in a garage or shop then moving it inside a house is always a “thing” we have to deal with. We deal with it by using well acclimated lumber, designing and building with future movement issue in mind.

Understanding that and moisture issues, the problem with this top stems from:

1) Wide boards more prone to cupping.
2) Construction lumber is very wet & fraught with issues related to moisture content.
3) How top is attached to allow for movement. Not cupping, but movement across the whole top. If the top is firmly attached, something‘s gotta give.
4) Edges jointed square and cleanly. (One joint line has a crack where the glue line failed)

WNT gave an excellent explanation. 

Now the solution - no question the top has to be cut apart and redone. The question how radical. Even though It looks like one glue line is the issue, I strongly recommend you take the entire top apart b/c this top is not done moving & you only want to fix it once. 

I also strongly suggest getting quarter sawn or vertical grain boards like the on on the left. You find these mostly in wider boards - 2x10‘s or 12’s. They will to be ripped down and remove the center pith section, this will leave boards roughly 4-5” wide.

Rebel is correct in wide boards cup more.

Personally I done even consider growth rings. When I make a top I am only interested in grain direction and grain matching, the rings end up wherever. If the wood is acclimated and not too wide, it’s not going to be an issue - personal viewpoint based on experience. 

When he’s got the top apart and all the boards ripped to width, he needs to stack them up with spacers (stickers) in between and let the wood relax and dry out some more - 3-4 weeks. If at all possible stack the wood inside the house b/c that’s where it’s going to live. Not a bad idea to bind the pile together with a few cargo straps.

Attaching the top is just as critical. There are several ways to do it, I prefer buttons - small L shaped blocks that fasten to the top and go into a slot in the trestle (Google it).

If you could tell us what tools and machines he has available, that will help a lot in advising on prepping the glue joints.


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## Tony B (Jul 30, 2008)

One of the problems with the top is that it might be screwed down to the top of the leg frame straight in. Was there a slot made in the leg frame so that the top could slide back and forth in the slot with the expansion/contraction of the top rather than just a straight driil and attach? 
In addition to what others have stated, a lot could be said of the poor quality of the wood itself. This warping is evident also in the leg frames. Look at the top section of the center vertical piece and you can see the separation at the glue line. Also on the bottom horizontal piece near the foot - separation again at the glue joint. Same thing, more or less, at the right side x-members have separated from the center piece. 
The first thing to do is to remove the screws holding the top down to the upper horizontal leg frame member. That will relieve the strain of expansion/contraction of the top. The hole that the screw goes through the horizontal member needs to be elongated so as the top expans/contracts the top will slide along in the slot. 
I am not a pine person because of the low quality available. These problems can be greatly lessened if you purchase your lumber in "premium" grade only. Also, let the lumber sit around and acclimate in the area where it will ultimately be living befoore you start working on it.


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## Rebelwork (Jan 15, 2012)

I've worked with a lot of pine back in the late 70-80's 2x8's aren't well suited for table tops. There too large in w







idth and cup a lot. They must be down sized... a 2x2 or 2x3 would work better..
all this pine is from the lumber store..


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## Tony B (Jul 30, 2008)

@Rebelwork What grade of pine is it and is it the same quality that is available today?
The reason I ask is because my first experiences with pine really turned me off to it. IIRC, I did buy a cheaper grade..


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## DrRobert (Apr 27, 2015)

The ponderosa pine my supplier carries is pretty nice stuff very stable

Jay Bates builds furniture out of SYP he gets 3-5” quarter sawn boards out of 2x12‘s. Personally I think it’s ugly looking but to each his own......


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## Rebelwork (Jan 15, 2012)

Tony B said:


> @Rebelwork What grade of pine is it and is it the same quality that is available today?
> The reason I ask is because my first experiences with pine really turned me off to it. IIRC, I did buy a cheaper grade..


Just regular pine . Cant remember, maybe #3 and in 1x4, etc was #2. Same stuff I assume they stand up at HD. In the day it was keep outside 50 cents a running foot on 1×12. . On a good day you could find enough. Always a good day when a fresh bundle gets opened..

Mainly just lumber bought and used on the exterior of a house prior to pain't ..


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