Cavity Supports for Composite Objects with Elements Protruding from the Underside
Duck decoys present an interesting challenge for storage because of protruding weights, keels, and leather loops on their bottoms (fig. 1, 2). When the decoys were in use they were often floating in water, but on solid substrates these elements prevent the decoy from resting in a stable position (fig. 3). While this mount design was developed for use with decoys, the concept could be applicable to other three-dimensional objects that do not have a level base.
This twist on a sink mat for three-dimensional objects is easy and affordable to construct as it is based on utilizing existing scraps and off-cuts of high quality archival materials.
Due to time and staff constraints, the mounts would function within existing storage spaces yet have minimal visual impact, clean lines, and blend in with the white exhibition cases for use on display.
Emily M. Wroczynski
5555 Shelburne Rd
Shelburne, VT 05482
Tel: (518) 275-2133
Photo & Illustration Credits: Emily Wroczynski, Courtesy of Shelburne Museum, Shelburne, VT
These mounts are built up out of individual pieces of blue board and/or mat board to create a void or a recessed area that accommodates the size and position of various protruding elements on the base of decoys. Each mount is custom built because the size and placement of weights on the decoys varies. The shape and curvature of the decoy body also varies. Some of the mounts are built up out of single pieces of board with “doughnut” cut-outs for the protruding elements (fig. 4). Individual laminated blocks placed around the protruding elements work better for objects with curved bottoms (fig. 5).
All of the support blocks are adhered to an overall base so that the mount is a coherent unit. The base is the smallest footprint possible while providing sufficient contact with the object for support. White non-woven, smooth fabric is wrapped around the blocks to provide the desired appearance and serve as a non-abrasive barrier adjacent to the object.
Materials, Tools & Supplies
- Scrap paper/brown paper for making templates
- Blue board, 100% cotton rag mat board scraps
- Cutting mat
- Straight edge
- Box cutter (rotary cutter)
- Smooth non-woven fabric
- Double-sided pressure sensitive tape
- Bone folder
- Examine the bottom of the object. Determine if there are some local flat/level areas that would make contact with a support. Measure the distance from each side of the protruding element to the edge of the object base (TIP: It is helpful to examine the object in its upright orientation from table level in order to see where there are gaps between its base and the surface of the table).
- The mount must be smaller than these overall dimensions. Determine the outline of the mount base according to the orientation of protruding elements (TIP: Place the object on a large sheet of paper and the outline can be traced. Then the outline of the mount can be worked out on this paper template with reduced handling of the actual object).
- Measure the depth of protruding elements (TIP: this can be done with a measuring tape or qualitatively by placing pieces of blue board/mat board next to the protruding weight to determine the number of pieces necessary to match the depth.)
- Trace the outline of the mount on a piece of blue board or mat board (a paper template is useful here). This will serve as the base of the mount. Cut it out using a box cutter. (TIP: If the outline is curved use a rotary cutter. If a rotary cutter is not available cut small sections out at a time following release cuts to the edges of the material).
- Use measurements from step #1 to cut out individual rectangular pieces of blue board. Place one piece of blue board on each side of the protruding element. Adjust the size and outline of these pieces of board as needed (i.e. one edge may need to follow the outline of the object base).
- Alternatively cut out a second piece the same size as the mount base. Trace an outline to serve as the void for the protruding elements. Cut this out as in step #4. Check the dimensions by placing this single piece under the object. If there is not adequate space allowed for the protruding elements and/or if the board is not contacting evenly with the base of the object then make necessary adjustments.
- Use the single pieces of board from step #5 or #6 as templates to trace additional pieces. Cut them out and stack them on top of each other. Continue to cut additional pieces of board until the desired height is achieved to compensate for the depth of the protruding element. Before adhering the pieces together check the height and the fit with the object.
- Adhere the individual layers of board to each other using double-sided tape.
- Cover the exterior of the laminated block(s) with Hollytex or Reemay. If release cuts or seams are necessary try to position them in discreet areas. Make fold lines parallel the edges of the block for a cleaner look. Allow for overlap of covering material so that the covering can be adhered onto itself using double-sided tape.
- Adhere the laminated blocks to the base board in the appropriate positions.
- Write the object ID number in pencil on the mount in a place that is not visible when the object is displayed on the mount. Also write any relevant instructions (such as arrows pointing to and labeling the front of mount).
If the shape of the support blocks seems like it will be challenging to cover with Hollytex consider using only mat board in the desired color. Any rough or cut edges can be burnished with a bone folder. If you are not able to obtain a soft non-woven fabric, muslin may also work as a covering.
1981. Smith, Merrily A. Sink Mat. In Matting and Hinging of Works of Art on Paper. Washington, DC: Preservation Office, Research Services, Library of Congress, 14-16.