Materials and Methods of Preservation Framing - The Back of the Frame
We often install a strainer in the back of the frame for strength and stability. A strainer is similar to a stretcher, with one difference—a strainer's corners are not adjustable. One advantage of backing a frame with a strainer is that it can be easily removed and re-fitted without the use of framer's tools.
There are various ways of hanging frames: Screw-eyes and wire; D-rings with or without wire; picture rail hanging systems; and wooden cleats or aluminum zee clips, which are often the best for heavy works. For museum clients we have designed a special Tee Plate with a number of improvements over conventional hardware for screwing frames to the wall. Many museums prefer this hardware for secure installation. We carry these in our online store.
The frame should not hang flush against the wall. Bumpers can be mounted on the back of the frame or strainer to allow air circulation between the frame and the wall, which will discourage mould growth.
At Bark frameworks, for large and heavy works we install proprietary nylon web carrying straps so framed works can be moved with safety for the work, the frame and the art handler. These too are available from our online store.
The question of sealing frames is not clear-cut. Since one of our primary goals is to protect framed artwork from environmental threats such as atmospheric pollutants and abrupt changes in humidity, it stands to reason that a sealed frame would make a fine solution. But whenever we seal something out, we also seal something in.
To the degree that it is possible to seal a frame envelope, with Mylar backing and careful taping for instance, we will also be sealing in moisture, which may damage the work, as well as solvents off-gassing from the artwork itself.
Partial sealing techniques can eliminate some risks. One method, when the artwork has been overmatted, is to apply an appropriate tape around the perimeter of the envelope, overlapping the front of the glazing by about 1/8" and continuing around to the back edge of the back mat. In general, waterproof backing boards are preferred.
Sometimes it is prudent to seal the inner surface of a wooden frame. For this purpose, we may use a strip of rag board or Mylar. An even better vapor and gas barrier is MarvelSeal, an aluminized nylon and polyethylene barrier film.