Wear safety goggles to protect your eyes. Rent a mortar raking tool or pneumatic chisel from a tool rental company, if necessary. A small chisel and hammer can be used. The smaller the chisel, the less damage you will do to the bricks. Use water and a mask to cut down on the dust that you breathe. Try your best to avoid grinding the brick when you are removing the mortar.
If you brush is getting quite dusty, bang the back of the brush on the ground to shake the excess dust off. Purchase stiff and soft-bristled brushes at a hardware or homeware store.
If it’s a hot day the water may dry before you apply the mortar. If so, you will need to re-spray water to the gaps before applying the mortar.
If none of the sands are the right color, try mixing the different sands to get closer to the original mortar color. [5] X Research source
To make 1 bucket of mortar mixture, use 3 heaped trowels of sand and 1 heaped trowel of cement powder. This ratio applies to volume rather than weight. Always mix cement outdoors and wear a mask and gloves. If you buy pre-mixed type “M” mortar for foundations or pre-mixed type “S” mortar for load bearing walls, they will have 1/4 inch rocks in them that will prevent you from using a mortar bag to apply to the joints. In that case, you can use a pointer tool to push the mortar into the joints. Using a pointer tool is a lot easier than people think.
Ideally the mortar should be the consistency of porridge. If the mortar is too thick, add a little bit more water until it is the right consistency. Keep the mixture thick enough so that it can stick to the trowel. Scrape any sand or cement from the sides of the buckets into the mixture.
Tuckpointing or grout bags can be purchased from DIY or hardware stores.
Depending on the size of the area you are repairing, you may need to refill your bag with more mortar. Squeeze the bag hard enough so that the gaps are slightly bulging with mortar. Don’t worry if it drips a little, or looks untidy as you can fix this later. [9] X Research source
Start at the top of the chimney and work your way down to the bottom.
A striker can be purchased from DIY or hardware stores. You can also use a piece of copper pipe or a wooden dowel. If you use a small moist sponge afterwards it will fill in the holes, smooth out the mortar and leave a professional look. You can also carefully clean the bricks with a large sponge to leave a clean finish.
