- 1). Inspect the wall for cracks and loose sections. Remove the loose or cracked areas of mortar by striking a stone chisel with a hammer along the joints. Chip out as much of the damaged mortar as possible to allow for a strong repair.
- 2). Brush out the spaces between the cobblestone where you chipped out the mortar.
- 3). Fill the joints in need of repair with mortar by pushing it into the joints with the point of a trowel. Make sure that the mortar is packed tightly in between the cobblestones to form a tight joint repair.
- 4). Smooth out the joints with a striking tool by running it along all of the freshly repaired joints until the mortar is smooth.
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