Need help with split table top

[Gail O'Rourke]

Hi,

Last November I made a trestle table for a client - 8/4 pine - top size almost 4' by 8'
http://www.woodworking.org/photo/albums/userpics/13344/trestle1.JPG
(http://www.woodworking.org/photo/displayimage.php?pos=-1993)
They just called with a split. It is not on a seam. It is split on the top and the bottom of the table...about 10" long.

http://www.woodworking.org/photo/albums/userpics/13344/split1.jpg
(http://www.woodworking.org/photo/displayimage.php?pos=-4350)

There has been lots of movement on the table - you can see the breadboard end - this is the diagonal opposite of the split

http://www.woodworking.org/photo/albums/userpics/13344/split2.jpg
(http://www.woodworking.org/photo/displayimage.php?pos=-4349)


I suggested we wait a little longer to see what happens once we get more humidity with the summer coming. I offered to replace the top also - but don't want this to happen again. I assume that there was a lot of moisture in the wood that I didn't count on. And I also assume that the side of the table with the split was pinned too tight.

Any other ideas would be great - HELP
:(

[Lee Schierer]

Hopefully you attached the breadboard ends without any glue, or maybe just a little in the very middle. If you make it again, attache the breadboard ends with a dovetail across the width of the table. This will hold the end on, but let it move with seasonal moisture changes. My experience with pine is that it shrinks a lot since most of it is not kept indoors after it is cut. You may get some releif with the higher humidity days ahead, but I doubt the crack will go away completely. If you can free up the ends you could probably glue the crack shut and put the ends back on. You might also need to put another coat of finish on the top.

[Steve Clardy]

Looks like the breadboard end didn't let the plank move.
What grade of pine did you use?

[Alain Tellier]

Wow! that is a lot of movement for slab that size... I will venture out a guess.

The split might have been the result of elongated holes in the breadboard not being long ( or wide ) enough to take the amount of movement we see in your picture, thus trapping the top and sending the shear force to the opposite end, splitting the top.

You might want to wait ( the client might not )to see how the upcoming season change in humidity will affect the size of the split, altough it might not disapear completely, you might be able to repair it by working it into a small V shape and use sort of a wedge of the same timber to fill the split and touching up the finish.

Good luck!

[lou sansone]

sorry to hear that Gail
What moisture was the wood when you built the table? I think if it was not at 6% you were destined for this type of situation. The amount of movement shown on the BB ends is not excessive, but it does show that during the heating season the table top shrank more than when you had built it. My experience has shown that most wood will get down to 6% in a centrally heated house during the winter. If the wood is not at 6% when you build ( and it is pretty hard to get it there unless it has just come out of the kiln ) this can be the result if the BB ends grab hold of the top. one of the culprits can be finish that has dribbled down into the crack between the BB end and the top. Elongated holes are great, but will not overcome the issue of the finish basically gluing the ends to the top.

I try to monitor my moisture content, but often end up with wood in the 8 to 9 % range or worse in the summer. I have begun to consider a " touch up" kiln to bring the stored wood that I work with back down to 6% just prior to building.

I did ask a very respected cabinet maker ( does super high end homes ) about this whole issue and he indicated that he "strongly" recommends to all his customers that they climatically condition during the heating season just to avoid the 6% moisture issue.

I would say that if you do remake the top, you have to make sure your wood is in that 6 to 7 % range and not just take the word of the lumber seller

best wishes
Lou

[tod evans]

the way i avoid finish causing the ends to bind is to wax both my floating tennons and the stub tennon, all but the center where i glue. in these parts a 42" cherry top will move more than 1/2" between seasons so i try and use wood that`s acclimated to my shop for assembly( no meter here!) i try and cut breadboards during the summer months if possible so hopefully the wood is at the midpoint of its travel. then prior to assembly i`ll break the edge of both the table and breadboard with a plane so when the movement occurs there are no sharp edges left hanging for clothes/rags/skin to catch on....02 tod

[Gail O'Rourke]

Thanks for the input. I did not check the moisture of the wood when I made it....now I will when it's for something like this. I did everything the right way, it just didn't come together like I wanted it. I can definitely patch it, I want to see how the wood changes as the months warm up and hopefully, we can get by with that, the customer wants the "used" looks , so it may work out just fine.... just a disappointment. But, I learned a lot today and there will be more to learn with the fix.

Thanks, I am going to print this out.

[Doyle Alley]

If you want to try and repair that crack, try using a shop vac. Have a helper hold the shop vac hose near the crack on the bottom side. You drop glue into the topside of the crack. By putting the vac hose closer or further away from the crack, you can regulate how much and how fast the glue is pulled into the crack. When the crack is full of glue, clamp it. Of course, this is all dependent on solving the source of the crack in the first place.

[Cliff Rohrabacher]

Two things come to mind:
1.) somehow the customer let the humidity go wild.
or
2.) the wood hadn't stabilized (still a lot of movement tho').

The first guitar I made was of kilned mahogany. It hadn't however been stabilized well enough for a thin cross section application like stringed instruments. So, it warped and split dramatically after I built the guitar by over responding to himidity. Hard lesson to learn that.

Though I doubt such is likely to be the case with thick sections as a table top will be it still may have played a role. Sometimes wood needs time to stablize and kiln drying doesn't provide the time element.

Wood is, after all, a wild element.

[lou sansone]

the way i avoid finish causing the ends to bind is to wax both my floating tennons and the stub tennon, all but the center where i glue. in these parts a 42" cherry top will move more than 1/2" between seasons so i try and use wood that`s acclimated to my shop for assembly( no meter here!) i try and cut breadboards during the summer months if possible so hopefully the wood is at the midpoint of its travel. then prior to assembly i`ll break the edge of both the table and breadboard with a plane so when the movement occurs there are no sharp edges left hanging for clothes/rags/skin to catch on....02 tod

hi tod

good tip on the wax for the tennon.. I agree with you on the mid point for moisture as well. my thought was that this type of split happens when the wood shrinks to 6%. I was thinking that if I could build it at 6% then the only thing I would have to worry about is when it expanded in the summer. The problem with my idea is trying to get wood that dry.

lou

[Bruce Page]

I'd blame it on the cat :D

sorry, couldn't help my self...:o

[Gail O'Rourke]

Anyone want to come to the bonfire?

ha ha - seriously, thanks for the tips. I am sure in the morning it won't feel so bad, but right now it feels horrible. But don't worry, I am not going to sell my tools yet...I love a challenge.

[Todd Burch]

Looks like a classic case of using construction grade pine, which is only factory dried to ~19% MC, and, is not the best cut for furniture grade projects. Depending on where "Hometown America" is, you should find out what your the EMC (equilibrium moisture content) is for your area and dry the wood to that MC. Search this forum for more on this via "equilibrium".

I had the same thing happen with a trestle table I made for myself, although nowhere near the same degree. My mistake, however, was I purchased the hardwood at a proper MC, but allowed the wood to "swell" while it was in the shop. After taking the finished top inside, it shrank over the next month,. Now, I have about 1/32" on each side where the breadboard ends are proud. Next time, I'll "deliver" the top unfinished, wait for a few weeks, then quickly adjust the breadboard ends and finish.

Todd

[Todd Burch]

...And the biggest question of all... WHO LET'S THEIR CAT ON THE TABLE WHERE THEY EAT??? GROSSSSSSS.

[Greg Heppeard]

the customer wants the "used" looks ,


Gail,

Would it be possible to use a butterfly patch with this? It would add stability and add to the "used" look.

[Bill Lewis]

I'd blame it on the cat :D Ya' beat me to it!

[Dana Van Pelt]

Excellant Idea.....a butterfly patch would look great adding to the "used" theme" I built a cherry blanket chest that had a split in the wide board and I put a series of butterfly joints down the crack....made it look like a kites tail.....the customers loved it.....good luck

[Ben Roman]

Other than the Crack The Table looks great.. I will probably use this as a example when I build a patio set out of mesquite.

Ben

[Todd Burch]

Now, Ben, are you just saying that because you KNOW Mesquite has a 2% shrinkage from fully wet to fully dry, or are you just partial to the wood? ;)

Todd

[Larry Norton]

Gail, it looks like you should make a trip to Hicksville!

[Ian Barley]

Gail - I have nothing to add from the technical point of view but know only too well the feeling that follows the news that one of your products has "failed".

It probably happens to me once or twice a year (on a base of 300+ of product shipped annually I have learned to accept it). The first reaction is always to look for what you did wrong and then to start giving yourself a hard time for it. The truth is that this is wood and it does stuff that is not always predictable. The wisdom you gain from this will make it more predictable but it will always come at you from left field with something.

When it happens in the shop it is easy to grin/sigh/cry and move on. When it happens in a customers home I always worry that they think I did them wrong. My approach is , as yours appears to be, show them that you will do what it takes to put it right. If they see that this is your approach you can only rise in their estimation. My best repeat customer and most avid recommender is one of the people that was unlucky enough to have a failure but was impressed by how it got resolved.

Learn, resolve and move on is the only way to be.

[Kyle Stiefel]

If the wood is not at 6% when you build ( and it is pretty hard to get it there unless it has just come out of the kiln ) this can be the result if the BB ends grab hold of the top. one of the culprits can be finish that has dribbled down into the crack between the BB end and the top. Elongated holes are great, but will not overcome the issue of the finish basically gluing the ends to the top.

Lou

Lou,

I am actually making a BB table at this point. What would be the solution to having finish get in between there because a gap will exist regardless?

Thanks,
Kyle

[Carl Eyman]

As to the finish acting as an adhesive between the breadboards and the panel, I'd wax the end grain of the panel and the shoulder of the tenon on the end cap and hope any finish that leaked down would not adhere to the wax.

[Gail O'Rourke]

Boy, I spent the day out of the shop and on my kids field trip and at little league games. I took a run this morning and thought about all my options....I will do as I told them and call them in a month, see how it looks then try to schedule a repair around a vacation they may be taking so that they won't be without their table too long.

This wood was furniture grade, but I didn't check the moisture. Ah well. I think that it is repairable- One of the reasons why I would like to repair or resuse this table as opposed to making another is that this one is already acclimating to their home....so I am going to see what I can do about it.

Thanks for all the tips today also, sorry it took me all day to check back in.

Have a great weekend everyone.

Gail

[Ed Frie]

...And the biggest question of all... WHO LET'S THEIR CAT ON THE TABLE WHERE THEY EAT??? GROSSSSSSS.

Todd, I'm thinking you better not come over to my house for dinner. :)

Let me guess, you don't own many cats. Cat lovers know who rules a household and it isn't the humans. Subservience comes with cat ownership. ;)

[lou sansone]

As to the finish acting as an adhesive between the breadboards and the panel, I'd wax the end grain of the panel and the shoulder of the tenon on the end cap and hope any finish that leaked down would not adhere to the wax.

I agree with carl, and it was the advise my respected friend Tod also gave early in this thread

[Alan Turner]

Gail,
I too was thinking of using a Dutchman or two for the fix. One over the crack itself, and one at the end of it to keep it from running. It would be a great look on a country sort of piece. If your clients like the idea, let us know if you need any help with this approach. There are ways to do it where it is pretty quick. Unfortunately, a refinishing, at least in that area, would be necessary.

[Roger Wilson]

Everyone is focused on the breadboard and the moisture content of the table top. Another possible problem could be in how the top is attached to the trestle. I assume Gail did this properly (would like to know how though) but the top could have gotten hung up on the attachment to that side of the trestle.