"dnoyeB" wrote in message
...
This time around I plan to create miter joints on the corners of my
stereo cabinet frame. I will also be creating a frame for a projector
screen and I plan to miter that as well. ...
.... What type of *new tool* to I need to support glueing /
clamping these corners up? (admitedly if I can do it without a new tool
that will work too)

It is a difficult one.
The very best way I know to clamp mitred frames:

Glue, screw or nail little 45 degree blocks on the outside of the frame near
the joints so that you can put a g-cramp directly across the joint and press
it properly together.

Does that make sense? If not I will draw it and post it for you on the
pictures group.

Tim W