SPRING 2014 ___________________________ 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. (c) 2014 Period Furniture Conservation LLC. All rights reserved. |