A brick wall is only as good as its joints. Those are the weakest points, most subject to penetration of damaging water. Joints must be properly finished or "pointed" to make the wall secure and long lasting. Joints that have been damaged or in which mortar has deteriorated from time and weather must be repointed or "tuckpointed." Special tools are required for this work.
The basic bricklaying and pointing tool is a trowel, but not all trowels are the same. Many styles are available with triangular blades that vary in length and width. Some are best for spreading mortar on brick faces for joints; others are thinner and have sharper points. Those with the thinnest points are best for pointing; after the brick is laid, the point of the trowel is run through the mortar to push it into a V shape. For some walls, such as those to be covered with other facing, this trowel pointing is adequate.
A standard finishing tool for brick mortar joints is called a "slicker." This tool has a long narrow blade that will fit inside the mortar joint. Several styles of slicker are available, depending on the finish wanted. The most basic is simply a long, narrow steel blade in a wooden handle. It is inserted into the fresh mortar and pulled through the joint to depress the mortar firmly inside the brick edges. It is frequently used in tuckpointing to replace deteriorated mortar.
The best mortar joint is a concave joint, which has the mortar compressed into a semicircle so water that enters at the top drains out the bottom of the joint. It is formed with a special slicker, usually thicker steel than the standard long-blade slicker. It has a convex shape so that when it is run through the mortar joint, it creates the ideal concave. It is used on both horizontal and vertical joints between bricks.
Another tool, called a V-joint slicker, forms the second best joint, V-shaped mortar, like the concave, sheds water out the bottom. V-joint and convex slickers are sometimes combined, one type on one end of the tool, the other on the opposite end. The V-joint is used just like the convex, pulled through the joint to compress the mortar into a V shape, both horizontally and vertically.
Many special pointing tools are available for special joints and purposes. They are called such things as grapevine jointers, Hubbard jointers or Venice slickers and are used to form special types of joints like the grapevine or raked joints. These mainly are used on internal brick walls. Combination tools also are available that can make several different styles of pointed joint.