I finally found the time to cut down the two plywood cabinet boxes I mentioned a few weeks ago. I cut one of the "sides" first, planning to cut the other side next and then finally the back.
But as soon as I completed the first cut, the structural rigidity of the cabinet was significantly reduced. Someone here mentioned hot-gluing scraps across the area to be cut, but I think that was mostly to keep the kerf from closing up. In any case, I woke up with time and energy... but without a glue gun.
For the next cut I made a kluge of two bar clamps. One was inside the box, configured as a spreader - pushing the sides of the box apart. The other was outside the box, pushing in. I figured the second one would be needed to keep the spreader from getting loose as the cut weakened the side wall of the box.
The setup worked OK, but it really offended my sense of How Things Ought To Be. It had gotten late by that time and I waited until this morning to cut down the other box. '
One of the things that I like about being a novice woodworker is the "puzzle" aspect of it. There's always a problem to solve. And my brain seems to continue working on the puzzle even when I'm not actively thinking about it.
This morning I had a flash of inspiration. Here it is:
[click the "Next" button to see it attached to the cabinet]
I fashioned a temporary pine "crossbar" to span between the two sides of the cabinet while I made the cuts and held it in place with "corner clamps". It worked well, and if I'd had a bunch of cabinets to cut, I could have transferred it from one to another easily.
"Sleep on it". Works every time.
Of course, here is where someone will likely chime in with a solution that's better, cheaper, quicker, prettier, better-smelling and generally better for mankind. That's OK. I'll still be proud of my "discovery".