@Mark Boyce posted:I trust you gave everyone an 'A'!
I didn't finish my Bachelors at night until I was 48. You only get an A if you give the professor what he or she wants.
I'm not sure I see how that clamp holds in 2 directions, though I know it does for holding a 90-degree corner.
Mark,
No, I didn't give everyone an "A". 
But a few got the benefit of the doubt (and more than they truly deserved).
The clamp is only a 90 degree one. Maybe these 2 photos will explain how it works. On the left, you can see the black rubber cushions holding the walls. On the right is the "backside" of the clamp. The right-angle corner is up against the backs of the walls. The thumbscrews apply pressure.
Does that help? It's a very handy clamp for exactly this sort of thing. I bought it a very long time ago in anticipation of constructing a large number of buildings. Haven't had the occasion to use it much until now.
George
