Wall Repair and Fasteners
Plaster or dry wall is
commonly used for walls. Other decorative materials such as plywood
paneling, paper, or just paint are used to help the appearance of the
wall.
Unfortunately, common
fasteners do not perform too well when used on plaster and result in
holes or cracks which are unattractive. Settling or shrinking of walls
also cause cracks.
Patching A Wall
Popping Nails:
The heads of
nails used to fasten plaster board to studs often pop out. This is
caused by moisture changes in the studs which squeeze the nail out. To remedy
popped nail heads, first drive additional nails about 2" above and
below the popped nail head. Drive the nails, including the popped nail,
until a dimple shows around the head. Be sure you hold the plasterboard
tight to the stud. Dust off all loose paint and plaster and fill the
dimple with patching plaster using a wide putty knife. Let dry and if
patch shrinks re-apply patching plaster. When patch is completely dry,
sand with fine sandpaper and paint.
Small Cracks:
Small,
narrow cracks can be filled with patching plaster. First remove loose
plaster and with an ice pick or knife, clean the crack so it is wider
at the bottom than on the surface. This allows the new plaster to stick
better. With a brush or damp cloth remove loose plaster dust. If water
mixed plaster is used dampen the crack.
Fill the
crack with patching plaster using a criss- cross motion to work it in.
With the wide putty knife feather the edges of the patch, about 2" on
each side of the crack, so it will be less visible. When dry sand
lightly and paint.
Large Cracks:
When the
crack is large the wet plaster will not stick. If this is the situation
buy a roll of patching tape at a paint store. Clean off all loose
plaster. Fill the crack with plaster and press the perforated tape into
the wet plaster with a wide putty
knife.
Squeeze out any excess plaster so there will not be a lump in the wall.
Let it dry, sand lightly and paint. A coat of sizing will make the
paint stick better and look better. Holes Through The Wall: If there is
a large hole through the wall patching plaster will not stick.
Two methods can be used:
The First Method:
Mark a
rectangle on the wall which includes the hole. With a knife or key hole
saw cut out the rectangle being careful not to break it. On a scrape
piece of plaster-board copy the section of wall. Then mark a frame
about 2" wide around the section of wall. This is the size of patch to
cut. After cutting remove the paper on one side and the plaster from
the frame around the patch The 2" frame of paper will stick out like an
ear all around which will hold the patch in place Spread patching
plaster around the edge of the hole and around the edge of the patch.
Put the patch in the hole and press the paper ears into the plaster and
hold it while it sets. Sand lightly and paint.
The Second Method:
Cut a piece
of metal plaster lath or heavy screen larger than the hole. Fasten one
or two wire ties to the lath and insert through the hole. Pull the lath
up behind the hole and wire to a stick of wood placed across the hole
on the front side of the wall. Moisten the edge of the hole and spread
a base coat of patching plaster to within 1/8" of the finished surface.
Roughen the surface with a stick or nail so the finish coat will stick.
After the base layer is dry remove the stick and clip the wires close
to the surface. Trowel on the finish layer being sure it is flush with
the wall surface. Let it dry and then paint. If the patched area is
large apply a coat of sizing before painting.
Fastening to Plaster Walls:
Lightweight Object or
Pictures - Very lightweight objects can be supported with a piece of
tape. The wall must be smooth, clean and dry. The glue is affected by
humidity and may let loose so do not hang anything that will break with
this kind of fastener.
Objects with a wide variety
of weight can be supported by a metal hook on a long tapered nail
driven at an angle into the plaster. These come in packages of three or
four and in different sizes depending on the weight to be supported.
Medium Weight Objects:
Some kind of insert, plastic,
fiber,
wood. or lead can be used with a sheet metal screw. Drill a hole just
large enough to be able to tap the insert into the hole. Tap the insert
into the hole until it is flush with the surface. Turn a sheet metal or
wood screw into the insert. Usually these inserts come packaged with
the right size screw for the particular insert. It will also tell you
what size hole to drill.
Heavy Objects:
Heavier
objects can be supported with a molly bolt or toggle bolt. Drill a hole
through the wall to fit the size of molly bolt -- be sure not to get
the hole too big or you may have difficulty turning the bolt without
having the connector turn. If the only
drill is too small, use a
small screwdriver, knife, or other object to ream out the hole until
the fastener will slide in snugly. Push it in and turn the bolt
clockwise until it feels tight. Now the fastener has expanded and
should stay tight Remove the bolt and attach the object screwing the
bolt in tight. Do not over tighten or you may pull the fastener loose.
Remember plaster is soft.
A toggle bolt can be used
similar to a molly bolt but with less care taken when installing.
Select a bolt long enough to include the object plus the wall plus the
length of the toggles when folded up. Drill a hole through the wall. If
you do not have a drill: Drive a nail through the wall. Wiggle it until
it comes loose and you can pull it out. Put a small screwdriver, knife,
or piece of metal into the hole and carefully enlarge until the toggle
will slide through. Assemble the object on the bolt and push the toggle
into the hole until you can feel it spring open. (Now you cannot remove
the bolt without losing the toggle in the wall). Tighten by turning
clockwise.
A toggle bolt should
be used where the object will be drawn up tight to the wall because the
hole must be large enough to receive the toggle. The object should be
large
enough to cover the large hole that is necessary.
