Cutting, Dry Brushing & sponging
After joints are rolled, polished or raked, the mortar on the brick edges and face should be removed by cutting and dry brushing.
Well laid clean brick work is the key to a perfect finish
Examples of Melbourne bricklaying
Failure to brush leaves lips, ridges and eyebrows of mortar smear covering the brick edges. These are very difficult to remove once the mortar sets and will make the cleaning job look rough and give a ragged edge. The bricks below needed hand scraping and multiple applications of B10K to end up with a clean sharp finish. Each pass takes off a tiny layer from the surface of the mortar (and some bricks). However mortar beds will not appear acid damaged as B10K is much more gentle than Acid although there is a limit to the number of passes before the mortar becomes damaged. Please note, that if you have to remove 5-10mm (or more) of mortar from the brick face with acid then it will be difficult to stop it affecting and removing similar amounts from the mortar beds. Cleaning these bricks is even more difficult if there is any plasticiser and almost impossible if they are heavily plasticised.
Below are pictures of some typical work that is quite common in Melbourne. These bricklayers have stopped using jointing tools and they don’t cut the edges, there is no brushing and they don’t remove or clean splatter and none ever sponge clean. These processes have been eliminated to increase their speed and make more money. There is no consideration for the quality of the end result and they continue doing it because they are not accountable for, or don’t understand, the cost and collateral damage that will occur from cleaning this type of work with acid and pressure washing.
Sponging to clean bricks after they have been cut and brushed is one of the best ways to get a perfect finish provided you do it when the mortar is CRISP and use a clean damp sponge (NOT WET). Do not treat the water with Hydrochloric acid. HCl fixes sand (fine silicates), cement and lime deep into the brick face crevices which appears as an acid insoluble whitish deposit that is invisible when wet. A very toxic chemical (Hydrofluoric acid) is required to try to remove this “stain” aka “salts” but it is almost impossible to clean. This problem can be prevented by frequently rinsing the sponge out with clean or fresh running water (best option). Wet sponging heavily textured bricks can also push the mortar deep into the brick face so care must be taken. Alternatively, if you cut and dry brush all surface mortar with a firm brush when mortar is crisp the deposits and smear will be virtually eliminated, and allow B10K to give a perfect finish.