Whenever I use paper tape to cover drywall seams, I make it easy on myself by using tape that has been precoated with joint compound. As shown in the first drawing, I run the tape through a wooden hopper containing joint compound (I thin the mud to the consistency of thick mushroom soup). The hopper, which I varnished to make it easy to clean after a taping session, is mounted to a square of 3/4-in. plywood. I clamp the plywood to whatever convenient work surface is at hand.
The tape spool is mounted on the infeed side of the hopper. The spool spins on a dowel that is held in place by a pipe hanger. On the outfeed side of the hopper, I affixed a length of hacksaw blade for cutting the tape.
When I'm using this rig for paper tape, I install the roll and slide the paper through until it protrudes on the outfeed side. Then I fill the hopper about half-full of joint compound. I pull the tape slowly through the hopper, and if the mud is the right consistency, a layer about 1/8-in. thick sticks to the back of the paper.
If the job calls for outside corner beads -- the type that are part metal and part paper -- I remove the roll of paper tape, which allows me to run the comer beads through the V-shaped kerfs on the sides of the hopper.
Keith R. Sheppard, Monarch, Alta., ca