Attachment H - Exhibit Object Mounting Guidelines.pdf

EXHIBIT OBJECT MOUNTING GUIDELINES

A. MOUNTING OBJECTIVE

There are many different methods of constructing an exhibit mount (or bracket) for any one object. However, all mounting devices must be governed by the criterion that they provide long-term protection for the object while on exhibit. The exhibit mount is where the object comes into physical contact with the exhibit, and the careful design and construction of mounts is necessary to avoid introducing a new source of damage for the object.

The mount must be functional and as inconspicuous as possible. The observer’s eye should acknowledge the mount but not concentrate on it. Materials should always be chosen for their appropriateness to the job and their unobtrusive appearance. For example, when acrylic sheeting is used, edges should be smooth sanded and the size of the acrylic support should be as minimal as possible while still supporting the artifact.

Brass mounts should have smooth, finished edges without burr or sharp points. Fabric covered boards should have the warp and weft parallel to the edges of the square cut board. The corners of the board should have the fabric wrapped around them so as to be smooth and line up with the corner edge.

A properly mounted object is protected from slippage, jarring, and other movements due to air currents, ambient vibration, and visitor movement. Exhibit mounting is critical to the preservation of much displayed materials and requires a set of highly complex skills. It is convenient, when talking about exhibit mounts, to separate them into two categories which reflect 1) their complexity and the skills required for their fabrication, and 2) their importance to the exhibit object’s preservation.

CUSTOM AND GENERIC MOUNTS

Type 1: Custom fit, object specific mounts Require object handling, measurement and fitting Frequently require consultation with a conservator Require design and fabrication by highly qualified, mounting specialist

Type 2: Generic, non-fitted mounts

Require no object handling and fitting Require only rough measurements Generally require no consultation with a conservator Require no special qualifications of its mount fabricator

B. MOUNT DESIGN

GUIDELINES:

1. Avoid all unnecessary handling of the objects.

2. No objects can be altered or reformed to accommodate exhibit mounting.

3. Mounts should provide adequate support to prevent physical stress or unbalanced weight distribution on the object. The object’s center of gravity or original intended attitude should be considered.

4. No mount should be permanently attached to any object and easy access to the object should be afforded for curatorial maintenance and emergency removal.

5. The fastening system to the wall or deck must be based on a mechanical design or pressure-fitted and not adhesives or sticky substances.

6. The fastening system to the object must be based on gravity or a mechanical design and not adhesives or sticky substances. Nothing should be ‘sprung-fit’ attachment to the object.

7. Mounts must anticipate in their design the tendency for organic materials to droop, sag, or experience dimensional changes.

8. Vibration of the mount and abrasion from the mount should be minimized by the nature of the mount’s design, materials selected for construction, and by using appropriate padding and finishing techniques.

(see sect. C)

9. Susceptible objects should not be subjected to creasing and folding or deformation by the placement of heavy objects directly on top of them.

10. Fragile objects, including all textiles, should be supported over as great an area as practical.

11. The mount must secure objects which are displayed in the open to be reasonably secure from theft by construction of a ‘security mount (see performance specifications).

C. FASTENING AND MATERIAL SELECTION

1. Original objects must not be drilled, trimmed, tacked, nailed, screwed down or glued down (no use of museum wax, silicone rubber or tapes).

2. Fastening system must be based on gravity or a mechanical design and not an adhesive or sticky substance, nor can the fastening to the object be ‘sprung-fit’.

3. Original clamps, hooks, strings, straps already attached to objects should not be used for support or to take the weight of the object without consultation with conservation.

4. An object should never be forced to fit in a bracket, cradle or other exhibit space. Straps or brackets should fit snugly, not tightly. No exhibit mount should be crimped around an object to fit. (Brackets should support and hold objects, not distort or scratch them). Cradles should gently support objects, not compress them.

5. Exhibit mounts should employ inert materials, particularly in the areas of contact with artifacts. (See supplied list of acceptable materials.)

6. Mounts should not utilize unstable dyed fabrics and materials. These colorants can be transferred to the display object and therefore testing of fabric is required. All materials not on the supplied list of acceptable materials require an 8-week testing period once received by NMAI

Conservation Department, to see if they are acceptable for use in exhibits. Unacceptable materials require re-submittal of NEW choices for testing and enough time (at least 8-wks) to re-test.

7. Sharp or point edges or burr should be removed from all materials in close proximity to the displayed objects and appropriate padding materials used where necessary during the fitting process as well as in the finished mount.

8. Brass mounts are only acceptable with silver soldered or brazed joints.

Steel mounts must be welded.

9. A coating layer used as a barrier or paint layer is required for all exposed brass surfaces. Finishes to provide a barrier coat between the mount and the object or an aesthetic paint layer where the mount is visible must match the installation design color or the object, and be acrylic paint. (See attached list of acceptable materials.)

10. Only high quality padding and cushioning materials should be used:

polyethylene foam, polyester batting, polyester or acrylic felted materials, 100% cotton fabrics, acid-free buffered tissue paper, and other materials on supplied list.

11. Metal and wood products must be sealed with conservation approved coatings.

12. High grade, conservation approved mannequins or other supports may be used for the display of garments. They may be constructed and padded with inert materials (i.e. polyester fiberfill, polyethylene foam) or buffered with cotton fabric from direct contact to the object. Fabrication methods must be approved by the NMAI Conservation Department to assure that the garments so displayed will not be unduly stressed when the mannequins or forms are dressed.

13. Muslin linings and backing are often needed to reinforce and protect these garments and other textiles. Anything attached to or removed from the garment or textile must be applied by a qualified conservator.

D. WORKSPACE

1. Persons measuring, fitting or installing objects on their mounts will wear clean Nitrile rubber gloves (or cotton when required) to prevent soiling of the object. (Glazed ceramics and glass objects are the exception).

2. Work areas around the artifacts must be kept as clean and clutter free as possible. Daily cleanup is mandatory in Collections spaces.

3. It is understood that contractors will supply their own tools and supplies unless a different arrangement is agreed to in advance.

4. When several contractors are sharing an NMAI space, each crew will use only their equipment and supplies unless agreed to in advance.

5. SI and NMAI safety polices will be posted and all members of the crew will read, understand and follow.

These guidelines were put together by NMAI Conservation Department staff: Mount Maker Shelly Uhlir, and Head of Department, Marian Kaminitz. Much of the content is taken from the National Park Service Guidelines for Exhibit Conservation written by Toby Raphael. The paragraph on aesthetics is taken mostly from “Mount-Making for Museum Objects”, CCI, 2002. Any errors are the responsibility of NMAI Conservation Dept. staff.