When carrying out the fair-faced cutting of bricks (that is to say, making cuts that will be seen), the cuts should be correctly sized. Where they repeat, such as in a broken bond, they must also all be of equal size; failure to achieve this will result in deviation in the verticality of cross-joints and odd-sized cross-joints. The actual line of the cut should be neat and straight, with no spalling or damage to the brick face. The use of sharp cutting tools is a key contributor to this last point.
Standard cuts for quarter bats, half bats and three-quarter bats can be easily and repetitively measured and marked out using a ‘closer gauge’, sometimes known as a ‘bat gauge’. This is usually home-made from off-cuts of timber. They are not that widely used and most bricklayers, when measuring and marking half bats (by far the most common cut brick), will simply use the width of another brick as a ready-made ‘gauge’.
Fig. 147 Wooden closer gauge, also known as a bat gauge.
For neat, accurate cuts on good-quality facing work, a sharp bolster chisel and lump hammer are used. The brick to be cut should have a good
face and appear sound, with no obvious cracks, as defective bricks are more likely to shatter or break in the wrong place.
Measure the bat or closer required – for standard cuts, this can be done with a closer gauge – then mark the cutting line with a pencil or the corner of the bolster blade. Non-standard cuts, for use in a broken bond for example, will need to be measured with a tape and marked to the required size, with allowance for cross-joints. To save time and to ensure that all the cuts are of equal length it makes sense to measure and mark several bricks at the same time (see Fig 148). Start by lining up a number of bricks (in this case ten) face side up and square up the ends with a spirit level or straight-edge. From the squared-up edge, measure and mark with a pencil the two end bricks to the desired length, in this case 180mm. Line up the spirit level or straight-edge with the pencil marks on each end brick and mark the remaining bricks in between to the same length. This method not only saves time but also eliminates any error that can result from the common variations in brick length.
and mark the two end bricks
Fig. 149 Hand-cutting bricks on a piece of ‘softing’.
Place the brick marked for cutting on a piece of ‘softing’; this will take the ‘jar’ out of cutting and reduce the risk of the brick breaking in the wrong place, which can happen if it is cut on a hard surface such as concrete. Ideal materials for softing include rubber matting and off-cuts of carpet or old carpet tiles. If none of these materials is available, spread some soft sand about 25mm thick on top of a hard surface.
When cutting, gloves and eye protection in the form of safety glasses or goggles must be worn.
Place the brick face side up on the softing and strike the bolster once on the cutting mark with the lump hammer. The blow should be hard enough to mark the face but not hard enough to break the brick in one go.
Turn the brick through 180 degrees, with its common face uppermost, and repeat the process on the opposite side of the brick. Finally, turn the brick through 90 degrees on to its bedding face and cut again between the two original cuts. If the brick does not break at this point, which is unlikely, turn it over through 180 degrees on to its other bedding face and cut again. It is fair to say that the amount of power applied with the hammer needs to vary depending on the hardness of the brick being cut but at all times it is advisable to think in terms of ‘encouraging’ the brick to break, rather than forcing it. Too much effort will result in shattered bricks and excessive waste.
Any final trimming of the cut bat/closer that may be required can be done using a brick hammer or a scutch hammer fitted with either a blade or comb. Finally, unwanted brick debris should be cleared away as soon as possible to ensure the work area remains tidy.