Calling in the Wilderness. pt 1

Sometimes competition is a good motivator. We may choose to challenge ourselves, or enter a challenge with others. In these times we may find reason to do our best work as efficiently as possible. Having a paying gig helps that too, but rarely results in making something we would just like to make. In the modern world there are several furniture and art exhibitions that have a competition element. Many of my readers, like myself, are members of historical reenactment and re-creation societies. Often these groups have such competitions several times a year with one or two major competitions annually.

I recently entered several items in a regional championship (Kansas, Missouri, Iowa, Nebraska, small part of Arkansas) competition for my particular organization, and very surprisingly to me took the championship. Many present asked to have pictures and the documentation that supported my entries posted online. This and the next few articles will present those entries. I will note that some concepts are particular to the organization. In the overall, I find the documentation requirements have propelled much of my background knowledge related to woodworking. Even for one’s own benefit in learning the craft, I would recommend adding in depth research to the reproduction preliminary design phases of making a new piece. All three of the projects in this series were completed, including written documentation, in under a month while working 40 hour weeks. Deadlines are also great motivators.

With no further ado:

Book Press, 16th Century, Nuremberg

Bookpress imageA reconstruction of book press as depicted in the professional workshop  of Hanns Landawer (d. 15 August 1532) from the Landauer I housebook, folio 21 verso.

75-Amb-2-279-21-v.tif

Detail of Amb. 279.2 Folio 21 verso (Landauer I)

The book press serves two primary purposes during the process of bookbinding. During the preparation of quires, the press allows a folio stack to be securely held with consistent pressure while the quires are cut to uniform thicknesses. This is important as to allow a consistent edge on the pages once the book is bound. As sheets of paper are folded over one another, the center leaves of a quire find their edges beyond the plane of outer leaves. Planing or shearing them even provides a fairer edge than what occurs naturally in this process.
The press later provides firm and consistent pressure across the surfaces of the book when the cover material is adhered to the boards which provide stiffness to the cover. This is not at all unlike modern bench vises or double-screw vises of the same era except the action of the press is along a vertical axis rather than horizontal.
Threaded dowels and matching nuts provide the tension on objects placed between the cheeks of the press.

John Ammon Bookbinder

Woodcut by John Ammon, 16th Century, depicting a Flemish bindery in operation. Notice the two “vises” in the foreground. These are more similar to “modern” double screw vises than the Landawer press.

No extant book presses were found while researching this project. It is by likely conjecture, given the coloration of the vise in this image, that a light colored wood was used to manufacture such an object. The requirements of the cheek boards would be resistance to splitting and stability in flatness. The threaded dowels and nuts must be of pore-diffuse hardwood, lest the threads tear or crumble apart under stress. Even the stress of cutting the threads would compromise oak, ash, or most any common European softwoods. This leaves any variety of maple as the most likely choice for the screws and lower cheek. Simplicity of construction suggests that the upper cheek would also be made of the same material.
Maple was used to make the nuts and screws on this reproduction. Flat sawn walnut was chosen for the cheeks, as a large board of walnut had been acquired for another project. Walnut had the added benefit of not being easily split, and would accept threading across the grain without great risk of tearing under strain.
It is intriguing to note that in this form the nuts traverse the threaded rod while the lower plate should hold stationary and the upper cheek “float” between them. Most wooden and metal vises tend to operate with the screw turning rather than a nut to provide tension.

The cheeks were flat sawn from the mill, as would likely have been the same in 16th Century Germany. At that point in time walnut would likely have been imported from Italy. German woodworkers had also been significantly migrating between Northern Italy and the German Principalities during this time frame. Italian Walnut differs in color and slightly in texture from American Black Walnut. Given the availability of European species, a North American member of the same genus was preferred.
The boards were cut by handsaw, jointed and surfaced by planing. These handtool techniques are largely unchanged over the last two thousand years. Any indication of plane tracks were removed with card scrapers. A basic cruciform design was then carved into the top cheek for decorative effect. While there is no indication of this in the Landauer image, this designer took it as a time to practice compass layout and carving technique on a flat plane.
The boards themselves follow a 2:1 interval, an Octave in Boethian Design. The thicknesses of the boards were assigned as approximately one finger in thickness. This all appears in keeping with the proportions of the original as indicated in the folio page.
Meanwhile, the borders and “cross members” of the carving are based on 1/6th divisions of the long and short ends, with full, half, and quarter circles having a boarder.  Variations in the concentric arcs (borders) are proportioned at 3:2 and 4:3 the respective radii.
Threading the dowels was an entirely different endeavor. Historically it is assumed that threaded rods were cut by hand using a lathe. Nuts were then, as now, cut with a tap. Close scrutiny of the Landawer Folio suggests that the ends of the threaded dowels were tapered, however. While it could be an error of the artist, it is also possible that the ends were in fact tapered. This tapering is consistent with the preparation of dowel stock for threading with a “modern” threading box. Though it is inconclusive as there are no references to such a device until the 17th century, it is possible that the innovation of a threading box is significantly older. Most of the resources that reference cutting of threads describe metal screw techniques which are cut on a lathe due to mechanical characteristics of that material. Wood, unlike iron or steel, may be cut relatively easily with a threading box.
The dowels for this press were formed from square billets the length of a forearm that were turned to rounds on a lathe. The diameter of them was limited to the size of a commercially available wood threading kit, in this case, 1″. Two sets were made, the first was discarded as the maple was too dry and brittle to hold the threads and tore significantly during cutting. The nuts were cut from similar scraps of maple and bored with a forstner bit in a drill press. In the same way were the pass-through holes of the cheeks bored out. In 16th century Germany this would have been accomplished with an auger or spoon bit.
Once the parts were completed the device was assembled. It had been planned to tap the lower cheek to feed the threaded dowels into, then secure with a casein glue. A size error was made while boring the holes in the lower cheek, meaning a wedge and glue technique was required to secure the ends of the dowels to the bottom plate.

It was noticed in the original artwork that the screws are not placed equidistantly from the long arisses of the boards, but rather offset about one third the width from the “front” edge. This was initially believed to be an artists error of depth perspective. While this press was used in binding a girdle book, however, it was discovered that the cheeks begin to cantilever once pressure begins to be applied to a folio stack. Offsetting the screws toward one long edge would lessen this levering action and provide greater force on the working edge of the press. This refutation of “artists error” seems to support the plausibility of a threading box as mentioned above.
I would like to replace the lower cheek with one that is correctly bored to accept threading. Time and financial constraints denied the possibility of simply replacing the board once the error had been discovered. Operation of the nuts for driving the force of the press originally left much to be desired. As the threaded wooden rods dried further, the action of the nuts improved considerably.

Top Plate

Top plate removed for clarity of carved relief.

Additional information:
-Boethius, Arithmetica (and) De institutione musica, 6th century
-Description of the Duke of Urbino Writing Desk, Item W.1-1958, V&A Museum, London, England http://collections.vam.ac.uk/item/O58582/desk-duke-of-urbino-writing-desk/

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This entry was posted in Calling in the Wilderness, Design and Proportion, Medieval Tools, Projects, Reproduction, Tool Research. Bookmark the permalink.

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