Thread by Thread Tear Repair is a state of the art technique for repairing tears aiming to reestablish the continuity of the fabric weave, while also preserving the original texture of the painting. Thread by thread tear repair was developed in opposition to the quite invasive lining or patching techniques, following the principle of minimal intervention.
This re-weaving technique addresses only the damaged area. It consists in pairing and rejoining the broken threads with a soft, flexible adhesive, while at the same time, intertwining them to recreate the original fabric. Thread-by-thread reweaving is a labor intensive and time consuming technique and in spite of being appropriate for many torn paintings, sometimes is not a cost effective treatment.
In the thread by thread tear repair technique, the tools used are not very sophisticated, scalpels, tweezers, surgical scissors, entomological needles… Others can be made out of syringe needles curving the end with a pair of pliers and fitting them in a small brush handle as shown in the picture. Also a heated needle is very helpful, but the really necessary piece of equipment is a binocular microscope or a digital microscope. In relation to the adhesives, there are several suitable for this technique, the most frequently used is a mixture of wheat starch paste and isinglass.
And then, patience, lots of it…
After the repair of the support is finished, there are a series of operations that are usually necessary. Planar distortions are treated taking into consideration de adhesive used for the thread by thread tear mending. If a wheat starch/isinglass mixture was used, the humidity necessary to correct the planar distortions can ruin the joint. A temporary barrier using Cyclododecane applied locally can be useful to prevent the dislodgment of the joint. The same consideration is necessary for other processes like filling losses, inpainting or varnishing.
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