Mark Pfeifer wrote, snipped heavily:
After a year of debate (slab? laminate? buy lottery tickets and pray?) I decided
to do the Paul Sellers bench. If you?ve not seen the videos, it?s made of glued
up 2x4s or 2x3?s, with mortises and dados. I?m better with chisels than thin
fine saws, so away we go....To my horror, despite being COMPLETELY CLAMPED,
these sob?s managed to gap on me. ...When I cut one end of the slab for square,
instead of one nice loaf of wood, each of the 2x4?s fell off in sections as I
cut. . . . . . For the bottom of the slabs I cheated and slathered more glue
into the gaps and smoothed it all off with a hunk of thin plywood. For the tops
. . . . I don?t know. Part of me wants to plane 1/4? off and see if maybe they
just gapped on top . . . . maybe the glue dried funny? Maybe if I plane 1/4? off
the top my beautiful unitary monolithic slab is still there?


Mark,
I bring you comfort, but you may not believe it when you've heard me out.

This isn't the only workbench you'll ever make. So none of it matters.

Oh, I'm a fine one to talk. I've never made a woodworking bench, and at this
point I'm pretty sure I never will. (My bookbinding bench is different, I had to
make that, to house some paper drawers I was given.) But we all have sizes of
work we're comfortable at. My comfort size is a cube about two feet square. From
the fact you hand-planed all the wood for a bench so soon after starting with
planes, clearly a workbench is inside your comfort size. That means you'll make
more. Probably you'll end up like Chris Schwartz, knocking off a new workbench
every six months because you're curious about how the style works, and then
you'll have to build a barn to house your collection...

Sorry, I got carried away there for a moment. But the point is, don't sweat it.
Don't panic, don't rush into "cures", let it sit and think about it for a while.
You may have hit the kind of panic disaster where everything you do goes wrong
because you are tense, but you feel you can't stop because things are getting
worse. And, of course,they continue getting even worse because you are tense.
Feedback loop. The only thing to do is to put the whole project down, stop
worrying about it, -let- it get worse, let your muscles unknot. And after a
while---maybe another six months, maybe less if you're lucky---you'll go into
the shop one day and fix it without pause and without fuss. Hey, I haven't made
my own bench, but I've had plenty of projects that have gone wrong. Bad wrong,
and on customer work. See ye these scars?...  You learn to recognize the point
when -anything- you do will make things worse, and put it down.

Maybe the worst mistake you made was to glue the sheet of plywood to the base.
This is basically putting a layer of thick veneer on the bottom, and the one
rule of veneering is that you have to balance the pull. A layer of plywood on
the bottom means you need a layer on the top to balance it. But don't go out and
glue on another layer right away; that would be panic reaction to the feedback
loop. And some people seem to get away with unbalanced pulls on furniture, at
least some of the time. My guess is that planing wood off the top would also be
bead, since it would make the unbalanced, asymmetric pulls even worse. But, hey,
what do I know? I haven't made a bench. So let it sit while you wait and watch
and think.
If you are lucky the whole thing will fall apart. Sounds brutal, but I'm not
kidding. Then you can stop fussing, run the pieces through a tailed pl*ner, and
sticker them for another project. And go out to a real lumberyard and get some
better wood. Or wait until this lot of wood dries out a bit. You will end up
with a smaller bench if you do it that way, but that might be to the good. I
suspect that most people "over-bench" themselves at first, make something far
wider and longer than they need or will be comfortable. I certainly know what I
wanted and planned for would have been much bigger than what I have, and what I
have is bigger than I need. If it doesn't fall apart, you might eve want to cut
the pieces apart along the glue lines, separate them and remove the failed glue
and the failed surfaces all at once. Then wait. You can't rush green wood.

The great pioneering railway builder Thomas Brassey once had an entire viaduct
collapse six days after it was built. Eight million bricks worth. Liable to be
hard on a professional reputation, something like that. But he had the whole
thing rebuilt at his own expense, with improved design, and the rebuilt aqueduct
is still going strong nearly two centuries later. Brassey's reputation has held
up, too.

Cold comfort, I know. Would it help if we started swapping stories of things
that have gone wrong?
Tom ConroyBerkeley