Farmhouse table issues

Was the wood wet or something when you made it?    Could it be the normal seasonal expansion in the wood or something?  Paint is usually the best "sealant" to moisture, but shellacs, stains, varnish, etc. all serve to seal out moisture to some degree or another.  You can to make sure you completely seal up the wood surfaces that are exposed to the environment, of course.  If you've already built the piece, you might have to wait for the wood to go back to its original size before you apply a good seal.

The wood might have been wet, something to think about.

Thanks.

Can you post a picture of your table?  Did you use pocket holes or bisquits to join the 1x6 boards? 

Construction lumber is not dried to the same level that 1X lumber is.  The moisture content is usually around 19% which is dry enough to prevent mold growth, but still fairly wet.   The only real solution is to let the boards dry before use by storing them inside your home, or in your case removing and reattaching the boards now that they have shrunk.

Dan,  What do you mean by 1X lumber...kiln dried?  Also, how long would you suggest letting the construction lumber dry inside the house?

1X lumber as in 1x4, 1x6, and so on.  The thickness is less so the drying process continues after coming out of the kiln more quickly than say a 2x4.  I would suggest letting the wood acclimate to the interior environment for at least 2 weeks.  Preferably the wood will be stored flat for a couple of months before being used. The amount of time will vary depeding on the initial moisture content, the time of year and the storage conditions.  It's a good idea to buy wood well in advance, stocking up when there is a good/great price and letting it dry so when the right project comes along you're ready.

Thanks everyone.  The wood had been stored on our deck (covered) but still outside.  So it must have still been wet.   We didn't use any pocket holes or anything to join the boards together.  Now that we've built this one, if we ever want to build it again I'll take your tips and let the wood dry inside and join the boards as well.

Hi Rawheid,

Do you have a backyard with level terrain?  If you do end up remaking this table, you could use the first one as a picnic table outside :)