Make sure the surface of the drywall is clean and smooth. Avoid using the tapered edge of the drywall board for this application. Measure and cut the Muddable J-Bead to length. Subtract ½” for vertical applications. Dry fit the bead to ensure the optimum fit.
Position the mud leg of the Muddable J-Bead so that it is facing the room’s interior. Slip the J-Bead over the edge of the drywall until both edges meet.
Install the drywall equipped with the J-Bead using screws as normal.
Staple the Muddable J-Bead every 6”- 8” with ½” staples while applying pressure by hand to keep the bead tight to the drywall surface.
Using a 6” taping knife, apply a coat of joint compound to the surface of the J-Bead’s mud leg. The use lightweight compound or setting-type compound in this step will reduce shrinkage and speed up the drying time. Let this dry completely, for several hours or overnight.
Using an 8” taping knife, apply the final coat of joint compound. Feather the compound beyond the previous coat. The use of all-purpose compound or topping compound will make for a more durable finish. Let this dry completely, for several hours or overnight.
Sand lightly with 120 grit sandpaper to finish.
Watch how the muddable J-Bead is installed in a Armstrong® module perimeter acoustical drywall system: