USG Manufactured Housing Handbook User Manual

Page 13

Then raise the knife blade to a
more upright position and scrape
off excess with a second stroke at a
right angle to the first stroke.
Compound should be level with
panel surface.

Tip
To determine if fasteners are
properly seated prior to finishing,
draw clean knife over each fas-
tener. If metallic ring occurs, drive
fastener below surface, being
careful not to break paper.

15 First Coat—Bead and Trim

Paper-Faced Metal Corner Bead and
Trim (Tape On)

Using a 6

Љ-8Љ taping knife, apply a

coat of S

HEETROCK

MH Brand

Setting-Type Joint Compound to
both sides of the corner. Keep this
coat as smooth as possible,
feathering it out 5

Љ-6Љ on each

side. Let dry. Sand sides lightly
where necessary. L-Trim and
Reveal Trim are finished in a

similar manner, except that only
one side is finished.

Other Types Metal Corner
Bead and Trim

Apply S

HEETROCK

MH Brand

Setting-Type Joint Compound
with 8

Љ knife onto one flange of

the corner bead. Work down the
entire length of the bead. Hold
knife at 45° angle and smooth
compound—one edge of knife
riding the metal, the other on the
surface of the panel. Compound
should extend onto panel a mini-
mum of 4

Љ. Repeat application for

other flange. Use same applica-
tion method for metal trim.

Tip
After filling first flange, the metal
corner edge may have some
lumps of joint compound. To
remove, run 8

Љ blade up the bead

while also moving it to the side. In
this way, the compound is contin-
uously moved aside as it is
scraped off.

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16 Second Coat, Flat Joints and

Fasteners
Tips
At this stage of finishing, tapered
joints and butt joints need to be
treated differently. Because
tapered joints provide a depres-
sion for the tape and compound,
there is a danger that the depres-
sion will remain incompletely
filled, resulting in a starved joint.

Butt joints, on the other hand, are
naturally crowned, because the
tape and compound have to be
placed above the surface of the
board. Excess compound will
result in a crowned joint.

To prevent starved and crowned
joints, two different techniques of
applying joint compound are
used. These are known as “cen-
tering” and “splitting.” You should
center a tapered joint by first run-
ning the knife down the center,
then up one side, then down the
other, then down the middle
again. This will ensure that the
depression created by the tapers
will be filled.

The tapered joint should then be
feathered, with the compound
spread out very thin at the edges.
To feather, press down on the
edge of the knife that is furthest
from the joint, and lift the other
edge very slightly.

When treating a butt joint, the goal
is to make the joint’s natural
crown as invisible as possible.
This is accomplished by finishing
the sides of the joint so that the
slope from the center of the joint
down to the level of the board is
extremely gradual. The technique
used to achieve this effect is
known as “splitting the joint,”
because you treat the sides first,
then wipe down the middle. On
each side, use the feathering
technique to make sure that the
thickness of the compound
changes as gradually as possible.

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