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Discussion Starter · #1 · (Edited)
I recently made a hard maple farm table that I designed my own but was a pretty similar style to a usual farm table. And recently I have discovered that the table I made is slowly coming apart in cracks. The biggest one I first saw on it was a 1/4" crack. Now when I build the table I thinking it was the best way, biscuit the whole table top. All the boards I used on the table top I biscuit and glued. I thought I used enough glued but obviously I hadn't used enough. As I was told by another woodworker, I apparently had to use a lot more glue than I did. But here is my question, what can I do now to fix it? In other spots on the table top there are cracks that also starting to appear.

I finished it when I got done building it going against and with the grain style of sanding, and there using semi gloss as the finish. I worked really hard on that table and would appreciate if anybody knows of a way I can save it.

Thanks in advance.

Jesse
 

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My best guess without seeing it and how you have the top mounted it is due to the wood shrinking. All wood shrinks as it ages and if the wood is a little green will shrink more. If you screw a solid wood table top to the base when the wood shrinks the screws won't allow it and the top will crack open to releave the pressure. It's better when mounting a top you run a dado on the skirt and install the top with clips like these so the wood is free to shrink. http://www.rockler.com/table-top-fasteners

The only fix is to remove the top and cut it apart and re-do the joints. You could still use the table top clips by using a biscuit cutter to make the slots.
 

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Jesse first we need good pictures up close and over all so we can see the full layout/design and close-ups of the cracks.

Without looking or knowing any more info it sounds as a typically happening thing with the trend known as the "repurpose" fad. The #1 common issue is MC (moisture content) not being proper in the building stage ALONG with the #2 issue of poor design or more common known as "lack of knowledge" of designing for MC changes.

Let's discuss the MC (IF you started out at 9% then this is old news BUT for proper info)...1st depending on the wood you used, fresh cut vs reclaimed/repurposed (barnwood, etc.), either are not MC correct for interior use without proper testing/drying. Green/fresh cut wood HAS to go through proper drying also, both styles final goal is approx 9% MC and most HAVE to be kiln dried UNLESS your one of the few that live in the few US areas that can be AD (air dried) down that far. The average ADing MC in USA is 12-14%...some higher and very few lower.

We have AD wood which in most cases the average ext MC/RH that it's dried in. KD fresh from the kiln @ approx 7-8% but normally balances below 9. AND then we have KD lumber that's not been stored correctly and it will return to the MC of where it's stored...and I've seen a few places that it basically wasted the KD costs due being to moist.

Next we have shop MC and it's affected by extreme temp changes ( keeping it heated for day use then dropping extreme over night then reheat AND not controlling a steady MC for stabilizing....extremely hard on wood movement and glue joints. The ideal is to be stable around 45% RH which matches most homes with H/Air.

3rd is the RH/MC to which a piece (your table) of furniture is kept in ....a house's MC.

DESIGN....I'm guessing you may have glued some cross-grain wood....meaning grains that run opposite directions @90 deg. This is common for a beginner or someone that's not been taught the problems associated with cross-grains and building for them. YES very few pieces of furniture can be built without having cross-grain BUT a good woodworker learns how to fasten without binding the movements.

NOTE ....ALL wood moves...ALL the time. from night to day and season to season...the amount all boils down to how you control temps and moisture.

Get us some pics and a little info on the wood..fresh sawn, AD, KD, reclaimed, etc., etc. build design and how it's fastened to pedestal...how it's finished, one side, both top and bottom, type of finish.
 
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Discussion Starter · #4 · (Edited)
I apologize for the late reply. As for the photo you all wanted of the table. here it is. I tried to take the best picture of it the best I could. And went ahead and marked the areas where the crack is and is starting to show in other places. Hope this helps more. having a bit of hard time figuring out the image thing. here it is and a close up the major crack. the Crack as you can see in the first one is quite long so I just did one area with the camera. table.jpg 2015-03-08 21.20.43.jpg
 

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How did you attach the breadboard ends?How did you attach the top to the base ?Did you also finish the bottom of the table top?We can see the cracks from the pics but it tells us nothing about the construction of the table.
I only see one pic.Looks like you tried to attach more?
 

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Discussion Starter · #6 ·
I'm just going to warn you guys that the table a a lot bigger than what my camera on my phone can take. without having to take apart the table. So I took photos of the different parts besides the table top. the table is by the way 64 long 40 wide.

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Discussion Starter · #7 ·
I finished the bottom the same way I finished the top. Sanding all the parts against the grain and with it. then finished it all with a semi gloss and polished it all. I used bolts to bolt the legs to the table top. I was trying not to use any screws on the top of the table and the only way I could do that is with the thought of using bolts to bolt the legs to the top. attaching it the legs to top. I used three bolts in each leg. and screwed the support beams in underneath the table top with 1" 1/4 screws to attach the support beams underneath the table top. hope this explains it more better. I've been looking at my notes from the products.
 

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So far with one pic and no info....

The wood was too high MC to start with....
and the bread board appears to be glued solid....
trestle/pedestal???
finish???
what time frame is from build to now???? that's huge drying cracks!!!
What's the lumber background history?? did you buy it from a mill???retail???cut yourself???reclaim???

OOOPPPSSSS!!! typing and timing overlap!! I'll look through post and reply.
 

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Discussion Starter · #9 ·
I got the wood from a local lumber supply that had special types of the wood not the just the usual types. so the wood I got was a Hard Maple. When I got it I thought it looked dried enough. But obviously it wasn't. I live in a small house that had a woodstove that I ended up getting rid of it also not too long ago. so probably because of the wood stove was there and I was able to use it at times. so that may of been contributed to the cracking. I keep my house at a normal temperature. I don't know if that would effect it though.
 

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Discussion Starter · #10 ·
I got the wood from the local mill lumber company. I don't know the history of the wood. and the table was build over a period of last spring 2014 through the end of the summer of 2014.
 

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A local mill company???? Is that like a sawmill?? or a retail KD lumber company??? I'm guessing it was a sawyard that AD's some lumber BUT not necessarily to any building specs.

Is all the skirt glued also??? What runs parallel with grain isn't a issue BUT when it's attatch to cross-grain at breadboard end it effects it.

The under supports, are they glued and screwed?? The way it's screwed it will not let the lumber move correctly in MC changes.

Average indoor temp is differ for each persons taste....MC is the concern.
Wood stove.....affect MC's horribly....NOT saying it can't be controlled via humidifiers ....BUT they dry the air extremely.
 

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Discussion Starter · #12 ·
Tim, its a local lumber company. I'm failing to see how this has anything to do with the cracks. or anything else unrelating to it. But yes its has been glue and no the screws underneath the support beams that are attached to the table top have not been glued. But as far as now I am just going to cut it apart as one person here said and restart it.
 

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Your construction method caused it to break. In post #6 bottom picture the boards screwed to the underside of the table was enough to cause the top to break alone. The top has to be allowed to shrink and that board prevented it from doing so. Also if the breadboard ends were glued on the end of the table this also could have contributed to the break. On a breadboard end you can only glue a small area in the center of the end. The rest of it is just fastened with either dowels or screws from the underside. Then where the screw or dowel passes through the tenon the hole has to be elongated to allow the top to shrink.

The wood stove could have accelerated the problem because they really dry the air out but the top should have been allowed to shrink.

The only solution is either cut that top apart and use the wood to remake it or start over completely. The board you screw to the underside you need to elongate the screw holes and use pan head screws with washers and not tighten them down too tight. The skirts also need to be fasten to the top in a manor which would allow the top to breath.
 

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Tim, its a local lumber company. I'm failing to see how this has anything to do with the cracks. or anything else unrelating to it. But yes its has been glue and no the screws underneath the support beams that are attached to the table top have not been glued. But as far as now I am just going to cut it apart as one person here said and restart it.
If the company that sold you the wood didnt properly dry it, you were working with wet wood, and after everything was assembled the wood dried out and shrink enough to cause cracks to form.

In other words, if the mill sold you lumber that was at 20% MC and you built with it immediately, and then moved it into an environment with 5% relative humidity, the wood continued to dry and shrink, and coupled with a design that wasnt too forgiving of wood movement, well, something had to give.

I believe thats the point Tim was driving at, but Tim, feel free to correct me if im wrong
 

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Discussion Starter · #15 ·
Alright, thank you Steve and epic. That's all I needed to know and was trying to find out. I appreciate the answers guys. As for the wet wood issue I guess if I am going to make something else from that company I am going to have to wait a while till it dries completely. Thanks for the info and it helped.
 

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I was only explaining why the MC incorrectness most likely happened AND that you (or anyone building furniture) can't just get lumber anywhere and expect it to be ready to build with. Your definitely not the first one that's been bitten by this "dry to touch" lumber lie BUT IF I/we as craftsmen here can get more correct info out there MAYBE there'll be less people having to go through what you've had to AND going to have to do to rebuild. If you noticed I gave you most of the correct answers BEFORE having enough info....ONLY because it's that common to happen.

IF we took a poll of the most common reasons for tabletop failure in builds it would look close to this:...1) incorrect wood MC content 2) incorrect joint build (like glued breadboard or non floating cross-grain especially on pedestal/trestle) 3) design failure 4) bad glue joint/failure 5) extreme shop to final destination MC change (not common BUT does happen).

I'm only here to help!! I was "throwed under the bus" before meaning I've been through this because 30+yrs ago some either wouldn't OR didn't know themselves to help me.

I forgot to say...NICE table design:thumbsup:...especially the trestle. Now that you know what went wrong....rebuild and enjoy!!!! AND post us the grand rebuild:yes::yes:.
 

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I am a newbie and have learned alot from this discussion. If I could ask a few questions for clarification.

I understand how screwing the top into the apron could cause cracking, but I don't understand how you can glue boards together for the tabletop without a joint (maybe a rabbit joint?) and not have them crack. I would think the boards would try to pull apart from one another as they shrink regardless of the glue.

I checked out the link posted on how to put together a table and most of them either use kreg screws and/ or glue to secure the boards of the top together.

Is there a joint to connect the boards of the table top that would allow them more room to move or is gluing the best option? Thanks in advance!
 

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Susan

The table top below is similar to the original poster, board edge gluing using Titebond Original only. You don't need anything other than just edge gluing the boards. The edges need to be square and flat, I use a jointer. When I built this, my boards were pretty wet and they were twisted, so I used a joint bit. But if you have good material, you don't have to bother about that, edge to edge with nothing else will last forever if done right.

I believe Steve in a post above, covered everything you need to know, I really have nothing to add. Only mention is that in the second picture below, from summer to winter every year, the bread board (board at the end) will stick over by as much as 1/2" each side and winter move back to match with the table again. You have to allow for this in your construction, otherwise something will crack somewhere.

The pictures were taken when built, 5 years ago. I expect this to last forever, without cracking.

Remember, wood moves across the grain only, not along the grain. So all your table top joints which are end to end are not subjected to stresses.

If you need more details, we will try and help.



 

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2) incorrect joint build (like glued breadboard or non floating cross-grain especially on pedestal/trestle) 3) design failure 4) bad glue joint/failure

Susan.... "but I don't understand how you can glue boards together for the tabletop without a joint (maybe a rabbit joint?) "

I didn't say NOT to use glue joints or any other style of joint....I meant use them correctly and in their proper place.

I think William covered the same style I use....GOOD flat glue loints for top BUT they can be done many ways. ALSO in the top he has a breadboard which CAN NOT be solid glued or the top WILL crack or bow somewhere.

"I understand how screwing the top into the apron could cause cracking". Screwing the top to the apron doesn't cause the cracking ....IT'S not allowing (in most instances we overbore/slot the apron hole) for joint MOVEMENT beneath the screw.

"I would think the boards would try to pull apart from one another as they shrink regardless of the glue. " ....This is why good MC control is so critical from the beginning. I CAN build from from "dry to touch" lumber using all the correct joints and glueing processes BUT I have to design and plan for the major shrinkage (and it WILL happen) AND there are major risks on enlarged joint openings and finish break down. BUT IF I built from correct MC lumber, in a controlled MC shop going into a controlled MC home there's NOT concerns of the little movement that WILL still happen.

Maybe the above helps ....remember all wood moves...just some more than others and proper joint use and design makes the difference between heirloom and failure.

By the way William....Beautiful table!!!
 

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Thanks so much for the additional details Willem and Tim. I had to read all the posts a few times but I think I get it now. I plan on building a similar table from reclaimed wood, but will get a moisture meter first to check the MC. then I will be sure to joint the edges and not to glue the breadboard. I would have totally lathered that breadboard joint up with glue so I appreciate the heads up. Thanks so much!!
 
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