Clamping board
Clamping board for laying out documents with pressed seals
Many archives hold large collections of parchment documents with attached or impressed seals. These collections present archives with particular challenges regarding storage and, consequently, space requirements. The most common storage method today is in so-called document pouches, less frequently lying flat in cabinets, and the exception is hanging storage, known as the "Cologne System." The latter two methods are not feasible in most archives due to space and financial constraints.
To ensure the more careful preservation of at least the oldest documents (9th to 13th centuries) bearing impressed seals, the Darmstadt State Archives decided in 1997 to remove this portion of the collection, along with all oversized documents and other valuable items, and store them flat in cabinets. Due to the documents' format, they are folded up to six times to fit into document sleeves. Folding was the standard method of storage at the time of their creation and only became a conservation issue when archives were tasked with their long-term preservation.
Two problems had to be solved in connection with this measure.
1. How should the documents be stored in the cabinets?
2. How can the tension caused by folding be relieved, especially in documents with embossed seals?
The first problem was solved by placing the documents on specially made trays. The creation of these trays will not be discussed further here. If there is interest, further information can be obtained from Mr. Hofferberth (see address below).
The second problem—how to relieve the tension on the documents (with the affixed seals) so they could be laid flat—required some consideration, culminating in the idea of the clamping board. The clamping board is a flexible modular system that can be adapted to the specific format of the documents and, when not in use, can be disassembled and stored in a very space-saving manner.
The individual modules are made of aluminum, measuring 25 x 25 cm and 5 mm thick. Holes have been drilled and threaded into these panels at regular intervals. Connecting strips allow the modules to be assembled to the required size. Spacers prevent the individual panels from warping when screwed together.
The following additional accessories are required:
• Plastic book screws
• Rubber rings
• Wooden sticks from laboratory supply stores
• Clamps made of Makrolan
• Hole screws
Once the necessary preparatory work (cleaning) has been completed on the document, the clamping process can begin. Cut a piece of cardboard (blotting paper) to the size of the document. The document will be placed on this cardboard, which will remain underneath the document during clamping to protect the seal. When attaching the clamps, ensure they are positioned as close together as possible. Minor tears at the edges pose no risk but must be covered by the clamps. The clamps are covered with blotting paper for adhesion, which can be easily replaced.
Thread the rubber bands through the two outermost free holes of the clamps and loop them once. Now, center the certificate on the plate and screw one of the eye bolts into the plate opposite each ring. Pull the ring through the opening of the bolt and loop it once. You can now apply the initial tension by turning the bolts and securing everything with the wooden sticks, inserting the stick through the ring. Several bolts can be secured with one stick. A single bolt is secured by screwing a second one into one of the adjacent threads. In this way, each rubber band, even those attached to a clamp, can be individually tensioned. This initial tension should not be too tight, allowing the certificate sufficient slack. Spray the certificate with a 50% water-alcohol mixture, ensuring the seal is covered. Do not spray directly onto the certificate; instead, let it fall as a fine mist from above. Wait a few minutes until the certificate has absorbed the moisture. Now the tension can be adjusted again until each rubber ring has approximately the same tension. This can be easily checked by tapping the rings. Depending on the room's climate, the document can be removed from the board after two days. As far as one can tell with parchment, it will now lie flat without tending to fold back into its original state.
It should be emphasized again that this method is intended solely to gently relieve the tension caused by folding in parchments with pressed seals. This is only partially possible with parchments that have hanging seals and a folded edge, because the folded edge is not completely secured by the clamps and can therefore curl up after drying.
complete tensioning board:
Set consisting of: 9 sheets measuring 250 x 250 x 5 mm
8 connecting elements 45 x 45 x 5 mm
4 connecting elements 45 x 25 x 5 mm
Clamps, eye bolts, nuts, screws,
Wooden sticks, rubber rings and brass book screws
Expansion modules: Increase the work surface by 1 segment and accessories.
Design by: Jürgen Hofferbert – Restorer, Hessian State Archives, Darmstadt
