One of the most remarkable things about the field of Conservation is its ability to bring together art and science, cutting edge technology and time-honored skills to preserve original historic or artistic works while gaining new insights into how they were produced and making them more accessible to everyone.
These aims seem very much at the heart of the remarkable project presented by William Hoffman in his paper which described the process of studying the manufacturing techniques of a Worthington steam pump excavated from the shipwreck of the historic ironclad USS Monitor which sank in 1862 and building a full scale working replica.
The two original Worthington steam powered water pumps from the Monitor, the earliest known examples of their type, are in remarkable condition considering the nearly 140 years spent in a marine archaeological context before their recovery in 2001. The pumps are nearly finished conservation and will be placed on display at the Mariners’ Museum USS Monitor Center, but the extensive corrosion of the cast iron and copper alloy parts has left them in a fragile condition. The project began to take shape out of the desire to convey the original movement and function of the object to the public in a way which was far more immediate than a computer simulation could achieve alone. I thought this seemed intriguing, and particularly poignant in a digital age when high quality digital renderings have become omnipresent.
Hoffman explained that by conserving, studying and documenting the evidence of the original materials and the molding, metal casting, fabrication, and machining processes used, an approach to making the replica was formulated, using a combination of traditional technical and art metal casting techniques, and the use of modern 3D scanning, CAD, and 3D FDM (force deposition modelling) printing techniques to aid in the pattern and mold making. No less important is the final machining of the parts, made easier by the use of modern computer driven CNC tooling. The resulting replica is well underway and it’s hoped that the fully working replica will be operational in the near future.
Hoffman’s talk was very engaging and made use of digital drawings, animations, and video footage of the replication process, all of which helped to relate a detailed process in a way which was easy for the audience to follow. The enthusiasm of the author and the team of conservators, museum staff, volunteer researchers, 3D scanning and printing specialists, metal casters, machinists, and industry representatives who had helped to make the project a reality came through clearly, as did the high level of interest in the use of the replica pump for multiple educational programs, highlighting the need for conservation of our shared heritage and the information and experiences it can bring to light.