Spring 2014

In the Studio: Functional Hardware & Fasteners

In the News

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Recent Treatments:

Annie Oakley's mechanical rocking chair

a period Korean low table

a 20c desk

a period refectory table

a 20c chair

detail of a period cabinet on stand

Principal & Senior Conservator
Yuri Yanchyshyn

In the Studio:
Functional Hardware & Fasteners

Last year was a banner year for furniture exhibitions in New York City. Surely one of the most memorable was the Abraham and David Roentgen exhibition at the Metropolitan Museum. In fact, the exhibition was so popular that the YouTube video depicting the Roentgens' Berlin Secretary Cabinet (http://www.youtube.com/watch?v=MKikHxKeodA) generated nearly five million hits. This also raised many viewers' curiosity regarding the unseen aspects of this furniture—the metal hardware and fasteners that permitted it to function so dynamically.


While the exhibit was running, we were asked to treat a notable example of American mechanical chairmaking — Annie Oakley's rocking chair. This chair was designed to collapse for travel and then to unfold easily. Doubtless it eased Ms. Oakley's busy traveling schedule as a member of Buffalo Bill's Wild West. Our treatment addressed this chair's folding mechanism and associated hardware.

An Overview

Mechanical furniture requires some type of fastener. In both wood and metal, these have been with us for millennia. Examples of Egyptian bronze nails have been dated to 3400 BC and there are mentions of nails in the Bible. Pictured on the left is a corroded "cut nail" which came into existence in the 19c when "slitting mills" began to automate what had been a laborious manual process.

Rivets are a more permanent connector which also date to the Bronze Age. These are very reliable fasteners, and have been typically used when there is stress at both ends of the shaft. A modern domed rivet is pictured in the center. It consists of a shaft with cap at one end; the other end is deformed into the shape of a cap by hammering. Screws are temporary fasteners, which have been around since ancient times, but not as long as nails and rivets, with some historians ascribing their beginnings to ancient Assyria and others to Hellenistic Greece.

What we do know is that wooden screws were used for olive oil pressing in the Mediterranean world, while metal screws appeared only later, at the end of the medieval period. They did not become commonplace until the end of the 18th century, when lathes for cutting them were invented. Pictured on the right is an example of an 18c handmade screw. There are numerous file marks, especially on the oval head, and the threads and troughs are not perfectly regular.

Other metal components have also played a historic role in furniture. Roentgen's mechanical furniture, for example, required metal springs. These were introduced in the 15th century as an advance in timekeeping instruments. Ever the masterful innovator, Roentgen incorporated them, along with weights, pulleys, hinges, locks, musical mechanisms and specialized brackets to make his furniture perform.

Conservation Issues

Without advances like these, the Annie Oakley chair would not have been possible. The folding mechanism required specialized brackets, riveted and screwed into the wooden elements, in order to function properly. When the chair arrived in the studio, however, one pair of brackets, originally attached with screws and now lost had been replaced with modern metal brackets, which simply supported the rear of the seat without permitting the chair to collapse and unfold.

We immediately realized that the brackets were not original, but had no clue as to what the original brackets would have looked like or why they were lost. Fortunately, a label beneath the seat identified the maker of the chair as E.W. Vaill of Worcester, Massachusetts and mentioned a patent number. Researching the patent led us to a schematic drawing of the chair, which depicted the shape and form of the bracket. From then on it was a process of trial and error to produce a prototype.

Starting with paper templates, we progressed to cut and shaped sheet metal and, finally, to having a machinist forge brackets to our specifications. Our testing revealed that they would work; however, it did not answer an important question: why did the brackets become lost? When we examined the chair closely during its mechanical movements, we realized that the brackets had to remain slightly loose to perform their function.

That led us to an important insight regarding the construction of the chair. The other existing chair brackets were still functional because they were held together by hammered rivets, preventing them from dislodging. Our brackets were attached with screws, a less reliable fastener for this purpose.

A Conservator's Ethic

At this point, we came to a significant juncture. Should we correct this design limitation by drilling through the wood members and installing a contemporary rivet to make the chair fully functional on a more permanent basis, or should we accept the design limitation,and inform the owner of this condition? As conservators, we are frequently faced with such decisions. In some cases, the choices are both difficult and limited.

In this case, we chose the less invasive, most conservative approach and decided to use screws, as in the original design.We carved fresh wood and adhered it into the worn wood cavities, added a slip washer and modern brass screws, and patinated the metal to match the other metals on the chair. We also informed the owner of this condition and suggested that excessive mechanical use of the chair would likely cause this issue to reoccur. The result is what you see in the photograph on the left.

This chair earned a patent for its unique design, and contributed to the evolution of mechanical rocking chairs, despite a suboptimal choice of fastener. Our decision was to remain faithful to its original design, while restoring its mechanical function.


In the News: The December 20, 2013 edition of the Wall Street Journal featured an article about Yuri Yanchyshyn, which can be found here info@periodfurnitureconservation.com _______________________________________________
Furniture Conservator Yuri Yanchyshyn has worked with wooden objects for over 30 years, from a cabinet-maker's shop to the laboratories of The Metropolitan Museum of Art. Private collectors, museums, architects and designers have all entrusted precious items from the 14th through the 20th centuries to Yuri's care, and institutions such as Institute of Fine Arts Conservation Center invite him to lecture. Yuri holds degrees from the University of Michigan and the California Institute of the Arts and received advanced training from the Amsterdam Academy for Restoration and the Smithsonian Center for Materials Research and Education.
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Yuri Yanchyshyn