Tips for Tuckpointing Old Mortar Joints
You will need a small hammer and a chisel small enough to fit into the joints between the stones or bricks. Using the point of the chisel, first scrape out all of the old loose mortar that your can. With air or water pressure, clean out the dust and small pieces. Don’t forget your goggles at this point. When all of the loose mortar is removed, the real fun starts.
You need to remove enough of the old mortar to give yourself about an inch minimum to fill with the new mortar. So, hit that chisel with the hammer and start moving mortar. Don’t overdo this. You don’t want to break your stone or brick. When you have etched out that inch or so of mortar, you are ready to clean it again. Don’t worry if the old mortar isn’t even. You will be filling it with soft material that will form to the contour of the surface of the old mortar.
You may want to use a good stiff brush along with air or water to clean out the dust. Take a little of your old mortar to the home store and ask the clerk to match it for you. If the clerk looks at you like you’re headless, go to a different store or ask for the department or store manager. They should have the knowledge and product to get a reasonable match.
You will need a sharp pointing trowel to insert the new mortar and a finishing tool that will let you match the contour of the mortar that isn’t being replaced. Realize that color and texture and shape will all change as the mortar surface weathers. Fill the gaps with enough mortar to allow for the proper type of finish to be accomplished. Work with a small enough area that you can complete the finish work within 15 minutes or so to keep the mortar from become too stiff.
After the mortar has dried for about 24 hours, come back with a soft brush and bucket of water and gently wash the surface to remove pieces of excess mortar around the edges. This will give you a slick nicely done job to brag to the neighbors about unless they are tuckpointers.
