"Swingman" wrote in message
...
"toller" wrote in message ...

Sorry, I left a word out.
Why not screw the shelf to the two legs

We're talking solid wood here, not laminate or veneer, right?

Why? You already know that solid wood of that width needs room to expand
and
contract with seasonal changes.

A design which calls for "screwing the shelf to the legs", unless I am
missing something in your description, does not appear to be taking the
dimensional instability of the solid wood into account.

Maybe I am not understanding the problem here. If I am, I would be grateful
for an explanation.

The two legs are held together by:
1) the top, which is parallel to the leg grain (pocket screwed, glue?)
2) the side panels, parallel to the leg grain (glued)
3) the shelf, parallel to the leg grain (pocket screwed)

Presumably the top, side panels, shelf, and legs all expand pretty much the
same rate; so there is no relative movement. The legs are quarter sawn, but
they are small and on the outside, so that shouldn't matter.

The problem that prompted the whole thread is 4) the cross grain support
(loosely pocket screwed).
I understand the support should have been done better; presumably mortised
to the legs. But what difference does it make whether the shelf is screwed
to the legs or not? The danger is that the shelf (and the legs and top)
will expand and stress the screws holding the support. The shelf will not
expand any more,or stress the support anymore, just because it is screwed.
That would not be true if this were August, since then I would have exactly
the opposite problem; but is it January.

(Thinking about it now, I could probably have avoided the problem by simply
making the shelf 1/16" narrower everything else. Does that make sense?)

So, where is the wood movement that I am not considering?
(I haven't put the top on yet, and am undecided about gluing it.)