# Book Matched Wood Separating at Seam



## dpierce988 (Dec 3, 2019)

Good Evening everyone,

I am new to the forum and consider myself a novice in wood working skills. I have made a few coffee tables using live edge slabs and have created some and sold some. Recently, my wife and I had someone book match two live edge slabs of maple together for a dining room table top. We planned on sanding, finishing, and building the legs for the table. I have basic tools and some space for most of my wood work but since we were going to be working with some hefty pieces of wood, we decided to have someone else do the book matching. The wood has been air dried for some time before the two live edge pieces were joined. We picked up the table top about 2 weeks ago and went on a vacation. We got back today and I noticed that entire seam of the book match has separated. There are two boards on the bottom that are screwed in that are keeping the pieces together. We were told that it was joined with high performance wood glue. I am at a loss of what to do now. There is some significant separation at the seam and it goes at the way through to the under side of the slabs. At first, I was thinking about cleaning out the separated glue and epoxying the entire seam (which I have done with smaller cracks in the past) but I feel like we would be using a ton of epoxy. Does it make sense to separate the pieces and rejoin the two slabs? I have never used butterflies, domino's, or biscuit joining. Re-gluing or epoxying is about as comfortable as I am at this point.


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## JohnGi (May 9, 2019)

The wood dried and shrank. Wood dries more quickly out the ends since the cell structure of a tree is basically intended to transmit water lengthwise. The centers of the two planks were not as dry as the ends, and the glued up assembly separated at the center as they shrank. If the glue line is stronger than the wood, and most good glue lines are, the wood itself will crack. You could fill the crack; but if the wood is not done drying, it will just crack some more.

It is striking looking wood. It needs to dry before you can do anything with it. The old rule of thumb for air drying is 1 year per inch of thickness. It is a good place to start for most woods in most climates. Someone with a moisture meter might be able to tell you more accurately.


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## Terry Q (Jul 28, 2016)

What do the two boards “that are screwed” on look like? Send a picture.

If the two boards are running perpendicular to the slabs, then that is why it cracked.


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## woodnthings (Jan 24, 2009)

*The joint needs to be redone*



dpierce988 said:


> Good Evening everyone,
> 
> I am new to the forum and consider myself a novice in wood working skills. I have made a few coffee tables using live edge slabs and have created some and sold some. Recently, my wife and I had someone book match two live edge slabs of maple together for a dining room table top. We planned on sanding, finishing, and building the legs for the table. I have basic tools and some space for most of my wood work but since we were going to be working with some hefty pieces of wood, we decided to have someone else do the book matching. The wood has been air dried for some time before the two live edge pieces were joined. We picked up the table top about 2 weeks ago and went on a vacation. We got back today and I noticed that entire seam of the book match has separated. There are two boards on the bottom that are screwed in that are keeping the pieces together. We were told that it was joined with high performance wood glue. I am at a loss of what to do now. There is some significant separation at the seam and it goes at the way through to the under side of the slabs. At first, I was thinking about cleaning out the separated glue and epoxying the entire seam (which I have done with smaller cracks in the past) but I feel like we would be using a ton of epoxy.* Does it make sense to separate the pieces and rejoin the two slabs? I have never used butterflies, domino's, or biscuit joining. Re-gluing or epoxying is about as comfortable as I am at this point*.





What I would do is run a circular saw down the seam using a straight edge to guide it. This will make certain that both edges are parallel to one another and on a large slab project, that is critical. The two boards that are screwed up into the bottom are an issue. They may/will prevent the wood from expanding or contracting, UNLESS the screw holes are elongated, a common practice for large glued up slabs. Leave them on until the seam is cleaned up. Them remove them and attach them correctly.

Once the seam is cleaned up you can reglue the slabs with Titebond 2 or 3, but make certain the slabs are flush across on top. Some cauls will keep them properly aligned. https://www.finewoodworking.com/2011/03/08/clamping-cauls-the-secret-to-great-glue-ups

This is getting a little beyond "novice" skill levels, but not impossible. We are here to offer advice when needed. You may need to purchase clamps, ratchet straps or cauls. Your other choice is to get the "someone" you paid to do this, to do it over correctly. :|


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## _Ogre (Feb 1, 2013)

the wood definitely needs more drying time, you can see by the way the glue is zigzagged in the gap that it never cured. imo the clamping method was incorrect too, the glue line is quite wide, possibly not jointed correctly. i am a big fan of biscuit jointers for this type of seam
leave the boards screwed on the back during the drying process, it may keep the boards flat. remove them and reposition them 1/4" away from the old screw holes


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## GeorgeC (Jul 30, 2008)

_Ogre said:


> the wood definitely needs more drying time, you can see by the way the glue is zigzagged in the gap that it never cured. imo the clamping method was incorrect too, the glue line is quite wide, possibly not jointed correctly. i am a big fan of biscuit jointers for this type of seam
> leave the boards screwed on the back during the drying process, it may keep the boards flat. remove them and reposition them 1/4" away from the old screw holes



I am not seeing the things that you say that you see. Would you please give a more detailed description.


Biscuits are good for helping with alignment. But in general they are not considered to be helpful for strength, unless otherwise the joint is not strong.


George


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## woodnthings (Jan 24, 2009)

*The back boards are an issue .....*

As I stated above the boards that are screwed onto the back may have kept each slab in place while they both shrank in from the edges, including the seam. This is why we want the slabs to be as dry as possible before a glue up and to not secure anything on the bottom side that will prevent movement. 

:vs_cool:


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## _Ogre (Feb 1, 2013)

GeorgeC said:


> I am not seeing the things that you say that you see. Would you please give a more detailed description.


that's not torn wood in the joint, i believe it is glue, very thick glue
almost looks like liquid nails


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## GeorgeC (Jul 30, 2008)

_Ogre said:


> that's not torn wood in the joint, i believe it is glue, very thick glue
> almost looks like liquid nails



After more careful look, I think you are correct. If so, something other than wood stress caused that seam to go apart. Unless the outside of the wood was held motionless and the wood shrank. 



George


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## woodnthings (Jan 24, 2009)

*That was my theory .....*



woodnthings said:


> As I stated above the boards that are screwed onto the back may have kept each slab in place while they both shrank in from the edges, including the seam. This is why we want the slabs to be as dry as possible before a glue up and to not secure anything on the bottom side that will prevent movement.
> 
> :vs_cool:





GeorgeC said:


> After more careful look, I think you are correct. If so, something other than wood stress caused that seam to go apart. Unless the outside of the wood was held motionless and the wood shrank.
> George



The wood was glued with" high performance wood glue" .... what ever that is? Liquid Nails? Gorilla Glue? Titebond? We need to have the OP contact the builder to find out what was used. :|


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