Mending photographs tears and cuts is an elusively simple conservation process. Tears or sharp cuts are physical deterioration aspects of photographic materials which affect not only the primary support but also the final image material and the binder layer.
In many cases, preserving torn photographs without mending is recommended, as it preserves the historical evolution of the material. In other cases, it is better or recommended to mend the photograph to preserve its physical integrity. And this should be done using specialized conservation and mending techniques, because wrong conservation using a doubtful technique or applying irreversible materials will increase the possibility of further damage to the photograph.
Whenever photographs (paper-based prints) are torn, the edges overlap and that leaves two-side ragged fibers that let you easily use reversible adhesive such as wheat starch or Methyl Cellulose (MC) to make an invisible repair. Before starting in the mending process, mechanically clean the two sides of the tear using a dry-cleaning pad or a latex-free soft eraser in a direction from inside to outside, then brush it with a soft clean anti-static brush.
When mending the tear, first determine the correct position for the two sides of the tear to overlap. If the tear is long and changes direction, mend only one direction at a time.
Place a sheet of Reemay® or Hollytex® -which allows ventilation but won’t stick to the paste- under the photograph, then glue one edge of the tear using brush (size recommended is 0) and move it over along the edge to get a light even coat of adhesive. Carefully fit the two edges of the tear together and plot off any excess adhesive using double layers of Reemay® and plotter paper. Remove the plotter paper and keep the Reemay® sheet on top of the photograph, and use a bone folder to carefully smooth down the repair. Place a wooden board and a lightweight on top of the photograph and give it time to dry.
Cuts, which have sharp edges, are usually harder to mend, because cuts with sharp edges never leave ragged fibers that let you easily paste it to make an invisible repair. However, gluing a strip of Japanese tissue paper, which is chosen for its flexibility and long fibers, using the following technique, could solve this problem:
First, tear an approximately 2 cm strip of Japanese tissue paper, along its grain direction if it is a mechanical made tissue paper, and make it slightly longer than the cut. Apply this strip tissue paper between the cut edges, so that half of the strip faces the front side of the photograph and the other half faces the back side.
Place the transparent Melinex® Polyester Film strip over the cut and draw a line over the Polyester Film representing the cut shape, then cut over the traced line to split the Polyester Film into two parts.
Lay the first part from the Polyester Film (which represents the front side cut shape) over the photograph front side surface (photograph layer) and under the tissue paper. Using a water cut technique or a scalpel, remove the extra fibers from the tissue paper leaving approximately 1 mm border from the photograph layer side, then apply the adhesive (wheat starch or Methyl cellulose for instance) over the tissue paper in one direction from the cut board to outside. Remove the transparent Melinex Polyester Film and place a piece of Reemay® or Hollytex® over the mend with a piece of plotter paper to draw moisture out of the mend.
Smooth down the repair using a bone folder. Place a wooden board and a lightweight on top of the repair and give it time to dry. A toning for the tissue paper may be required. Apply the same for the back side but this time leave approximately 3 mm border to give a stronger support to the cut.