Joints - expanding...

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ScottGoddard

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I built a small table (below) a few weeks ago. All of the exposed joints were clean and 'level / flat'. However, they seem to have expanded, only a small amount and not even, but they are now not 'level/flat', against the rails.

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Good point......What would have caused this? I am assuming there has been a small amount of shrinkage?
 
Sorry, its probably me but which joints?
When you say rails, do you mean what I would call the breadboard ends or do you mean the through tenons at the top of the legs?
 
The boards which make up the table top have shrunk in width. The ends have stayed the same length.
This is perfectly normal.
 
AndyT":2gp2go7p said:
The boards which make up the table top have shrunk in width. The ends have stayed the same length.
This is perfectly normal.
Looking more closely then I see what you mean.
Yes, you have movement across the grain (top) and probably none at all along the grain (rails).
As Andy says, perfectly normal and having just glued up a box lid today with breadboard ends I will probably have the same and so a good reminder for me to bring the lid indoors for a couple of days.
 
In spite of the fact that they have been around for many years, breadboard ends are not a happy mix with today's domestic heating and low humidity. If the moisture content of the top increases the ends will fall just a little short of the width, if the top dries the ends will project a little. In the highest quality work mitres are used at the ends of the boards to cover all end grain. This is disastrous if the top shrinks because the top will usually split at the root of the mitres. The problems can be reduced by storing the solid timber in the place where the finished item is to be sited when completed.
In the case of simple bread board ends the worst that can normally happen is that the ends will need to be trimmed level after the top has dried completely, or you can just live with the slight differences. You will also see a small shrinkage effect on the exposed corner joints.
 
AndyT":ml23u6ra said:
The boards which make up the table top have shrunk in width. The ends have stayed the same length.
This is perfectly normal.

I built it 3 mm in so if it did shrink it would be less noticeable...maybe it didnt work.
 
ScottGoddard":332blcny said:
I built a small table (below) a few weeks ago. All of the exposed joints were clean and 'level / flat'. However, they seem to have expanded, only a small amount and not even, but they are now not 'level/flat', against the rails.


That looks identical to something I just saw on TV on an Oak Furnitureland advertisement!
 
Mike Jordan":p3t24qvx said:
In spite of the fact that they have been around for many years, breadboard ends are not a happy mix with today's domestic heating and low humidity. If the moisture content of the top increases the ends will fall just a little short of the width, if the top dries the ends will project a little. In the highest quality work mitres are used at the ends of the boards to cover all end grain. This is disastrous if the top shrinks because the top will usually split at the root of the mitres.

I'd say mitres are pretty much disasterous if wood movement is in any way significant, because they are only 45 degrees at one level of moisture content. Gappy mitres look to me rather worse than a slightly out of line breadboard end.
 
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