The Monticello Association began restoring the original cast and wrought iron fence at the Thomas Jefferson graveyard in 2020. The Jefferson graveyard had required constant attention from the Jefferson family since shortly after Thomas Jefferson’s death since sightseers and others would break into the walled and gated cemetery to visit the gravesites and occasionally take souvenirs. In 1883 the U. S. Government built a new monument and a tall iron fence surrounding the cemetery.
All of the original cast iron fence posts were disassembled for restoration by Chase Architectural Metal and while the original castings were in the shop Richmond Iron made foundry patterns to cast posts for a new section of fence. The new cast iron posts were to be accurate reproductions of the original designs but taller and with a few other minor changes to ensure the new posts would not be confused with the original ironwork. To efficiently reproduce the original castings with all of the depth of detail and to incorporate the loose greek key details into the castings, the pattern makers at Richmond Iron created traditional foundry patterns with advanced elastomer loose piece elements to create undercut features.
Original Castings from Thomas Jefferson Graveyard Fence Posts
The original castings are highly detailed with deep shadow features that fully wrap around the post without cheating the design for the parting line and casting draft typically required for two part sand mold. Notice how the bundled spears and flutes in the post columns have a uniform profile all the way around the circumference of the post. We don’t know exactly how this was accomplished but there is some evidence in the castings that multiple hard loose pieces were used to mold the castings. There is evidence of typical sand casting artifacts of iron like parting lines and minor dross inclusions but the overall effect of a richly and deeply shadowed decoration of the cast iron posts is impressive and demands extra measures for reproduction.
Also notice how some of the decorative features of the post are accomplished by using multiple smaller castings that are assembled together by pins or other hardware attachment. Notice the fence post top has a bronze half ring casting with a classical scroll detail. Just a few bronze castings were found and most of the castings were cast iron. These hardware attached emblems provide rich and attractive details to the post, but they can suffer from accelerated corrosion or come loose over time since water can get in between the castings if the coatings fail.
We are not aware of a direct lineage of design detail for the iron fence at Monticello from Jefferson’s architectural designs except to recognize that Thomas Jefferson advocated the use of classical architecture in designs for government and public buildings like the Virginia State Capitol and the University of Virginia. The cast iron posts at Monticello have a Roman spear bundle design for the columns that may have been inspired by the more comprehensive use of this motif for the cast iron fence that surrounds the Virginia Capitol Square. The cast iron fence at the Virginia Capitol and Monticello both employ decorations from Roman temples and the Ionic order which Jefferson explicitly used for the Virginia Capitol buildings although both fences were later additions not directly supervised by Jefferson.
Artisanal Foundry Patterns for Accurate Cast Iron Reproduction
The foundry patterns made by the master pattern makers at Richmond Iron utilize traditional wood patterns with elastomer loose pieces to mold deep undercuts. When the sand molds is drawn the rubber loose piece separates from the foundry pattern and remains embedded in the sand mold half to be removed by hand. The rubber pattern can be bent or folded to get it to release from undercut details in the mold. This technique allows sand casting of deeply undercut features without cheating the design for casting draft. These designs could also be molded with hard loose piece patterns but multiple hard loose pieces would need to be used for some of the sections molded with one rubber loose piece resulting in more lines or seams present in the casting requiring hand chasing of the surface to eliminate parting lines.
The new cast iron fence post for the Jefferson cemetery is to be shorter than the original so only one Roman spear section length was used and we combined the fluted section into one contiguously cast column. Other castings were consolidated into fewer parts for assembly which reduces the labor required and improves longevity since water has fewer places to get trapped and coatings may be applied for a perfect seal. Although we used modern castable urethanes and rubbers to achieve production ready patterns, the woodworking and mold making techniques used by our pattern maker are very similar to the skills of the original pattern making in 1883.