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Last updated March 2004.

Manual Guide No. 28B (1992)

Marginal Materials (MM) Case

The MM case is a simple enclosure designed to provide stable security to damaged materials at the shelf. There are three types designed for slightly different circumstances, and all three are described here. However, the following are typical uses:

usable books which are too brittle to bind, yet not important enough to replace with film etc;
little-used damaged and/or deteriorated books marked for storage;
materials which are incomplete, but which cannot be rendered complete by the usual means (photocopy etc.);
rare materials, scheduled for extensive treatment at some later date.

The case must not be used as a means of avoiding necessary collection development decisions on relevance, replacement etc., or as a purely cosmetic measure to "tidy up" the shelves. Because permanent/durable materials are used, no modifications are necessary for rare items.

Materials.

An acid-free, permanent/durable board of approximately 20 point thickness. Map folder stock (10850) .020" x 30" x 40" from the Hollinger Company serves very well. Strong unbleached tape of approximately .7 centimeters (l/4"), the type I version; velcro coins from University Products for the type II version; P.V.A. adhesive.

Equipment.

If available, a conventional board shear, or heavy office guillotine which must be wide enough to cut across the board width; if not available, a knife and metal straight-edge should be used.

bone folder
1 pair scissors
1 steel ruler (preferably 18" long, showing both inches
and centimeters)
1 wood chisel, same width as tape
1 small glue brush
scrap binders' board

Measurement Formula, Types I and II.

The case consists of two pieces of board designed to wrap the item from front to back and from top to bottom. Assume as a model a book measuring 20.3 (height) x 13.0 (width) x 2.2 (thickness), shown as Figure 1. The first board is cut to the height of the book, by three times the width plus twice the thickness, 20.3 x 13.0 + 13.0 + 13.0 + 2.2 + 2.2 = 33.4, and scored and folded accordingly (see Figure 2).

The second board is cut to the width of the item by two and one half times the height plus twice the thickness, 13.0 x 20.3 + 20.3 + 10.1 + 2.2 + 2.2 = 55.2, and scored and folded accordingly (see Figure 3).

Though the formula appears complex, it should be remembered that the first board simply wraps around the width of the book, while the second board wraps around the book from top to bottom with overlapping flaps. Once the basic principles are understood, the boards may be measured simply by placing the book on the board, and marking directly with a pencil.

Construction. Type I, Tape Ties.

This type would be used with large heavy books in need of firm compression. The center section of board No. 1 is glued with P.V.A., and the center section of board No. 2 laid onto it and rubbed down firmly with the folder. Slots are now cut into the case at 4 centimeters from the nearest edge and fold, as shown in Figure 4, and tape threaded, as indicated, to form ties at the fore-edge. The book is placed in the case, and appropriate information written onto the spine, as shown in Figure 5.

Type II. Velcro Coin Fastener.

The general construction of this type is identical to type I, except that the flaps are secured by Velcro coins instead of ties. This type may be used in most books providing that the board selected has a hard, firm surface. If the surface is soft and tends to easily separate into layers, the type III case may be used. The positioning of the Velcro coins is shown below.

Type III. Fold-in Flap.

The general cutting and folding configuration for this type is somewhat different from types I and II. No fastening tape or Velcro is used as the case is secured by a folder flap. The cutting and measurement formula are as follows. The case is made up of two boards. Assuming the same model book as for type I, 20.3 cm. (height) x 13.0 cm. (width) x 2.2 cm. (thickness), the first board is cut to the height of the book, by twice the width and three times the thickness plus approximately 3.0 cm. for a flap. The board width is 35.6 (13.0 + 13.0 + 2.2 + 2.2 + 2.2 + 3), and is folded as shown below.

The second board is cut to the width of the book (13.0 cm.) by three times the height minus one centimeter, and twice the thickness (20.3 + 20.3 + 19.3 + 2.2 + 2.2) as shown below.

The two boards are glued together by applying adhesive to the center portion of the second board, leaving an unglued area slightly wider than the flap as shown below.

The book is placed in the case, and the flap inserted into the "pocket" created by the unglued strip as shown below.