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Back Figure 8-43.-Making a closure joint in a header course. | Up Builder 3&2 Volume 01 - Construction manual for building structures | Next Templet |
Figure 8-45.-Cutting brick with a chisel.
CUTTING BRICK
To cut a brick to an exact line, you should use a
chisel (figure 8-45), or brick set. The straight side of
the tools cutting edge should face both the part of the
brick to be saved and the bricklayer. One masons
hammer blow should break the brick. For extremely
hard brick, first roughly cut it using the brick hammer
head, but leave enough brick to cut accurately with
the brick set.
Use a brick hammer for normal cutting work,
such as making the closure bricks and bats around
wall openings or completing corners. Hold the brick
firmly while cutting it. First, cut a line all the way
around the brick using light hammer head blows.
Then, a sharp blow to one side of the cutting line
should split the brick at the cutting line (figure 8-46,
view 1). Trim rough spots using the hammer blade, as
shown in view 2.
FINISHING JOINTS
The exterior surfaces of mortar joints are finished
to make brick masonry waterproof and give it a better
appearance. If joints are simply cut to the face of the
brick and not finished, shallow cracks will develop
immediately between the brick and the mortar.
Always finish a mortar joint before the mortar
hardens too much. Figure 8-47 shows several types
of joint finishes, the more important of which are
concave, flush, and weather.
Of all joints, the concave is the most weather
tight. After removing the excess mortar with a trowel,
make this joint using a jointer that is slightly larger
than the joint. Use force against the tool to press the
mortar tight against the brick on both sides of the
mortar joint.
The flush joint is made by holding the trowel
almost parallel to the face of the wall while drawing
its point along the joint.
A weather joint sheds water from a wall surface
more easily. To make it, simply push downward on
the mortar with the top edge of the trowel.
ARCHES
A well-constructed brick arch can support a heavy
load, mainly due to the way weight is distributed over
its curved shape.
Figure 8-48 shows two common
arch shapes:
elliptical and circular. Brick arches
require full mortar joints. The joint width is narrower
Figure 8-46.-Cutting brick with a hammer.
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