Custom Mold & Casting Project: Eagle Head – Spring, 2014
One of the lesser-known aspects of Abatron, Inc. is the services that are offered by our custom mold and casting shop. We are able to take just about any three dimensional architectural element and recreate it by utilizing our polyurethane moldmaking products and a wide variety of casting compounds. During the spring of 2014, we encountered our biggest challenge thus far: a 1300 pound, stone eagle head, sculpted by Montana artist, Ken DeRosier. The impressive piece measured in at 36” tall, 24” wide, and 34” deep (from the tip of the beak to the back of its head). The base of the sculpture has an 80” diameter.
The sculpture as it arrived in our shop.
Our first step was to prepare the surface of the stone. A special sealant, Primkote 8006-1, was used to prevent the stone from flaking or dusting during the creation of the mold. Once sealed, the entire surface was coated with a release agent, Abhesive 15-B, which allows us to peel off the mold once cured.
Sealed and coated with release agent, Abhesive 15-B
Troublesome depressions in the carving were filled with modeling clay, which makes the removal of the mold much easier. Then MasterMold™ 12-8 was brushed on to the entire figure, capturing all of the hand-carved detail.
The modeling clay can be seen in the eyes of the eagle.
After the detail-coat of MasterMold 12-8 fully cured, the mold was built up by layering thick applications of a special modified formula of MasterMold 12-3 over the Mastermold 12-8. The thickness of the mold increases its durability and its capability to produce multiple castings.
Built up coats of MasterMold 12-3.
The next step in the process was creating the support mold, which is a shell for the mold to sit in while the castings are made. The support mold ensures that the flexible mold keeps its shape while the castings cure. Oftentimes, creating a support mold can be as simple as packing a plaster shell on top of the flexible mold. This one was much more complex. It was made in four pieces so that it could be easily removed and reassembled, and it utilized an epoxy and fiberglass resin system for extreme durability and strength.
The flexible mold was wrapped in plastic to assure that the support mold would release easily.
Once the support mold was removed, the flexible mold was unwrapped from its plastic, carefully sliced, and then peeled away from the sculpture.
Peeling away the flexible mold.
The support mold was then reassembled, with the flexible mold carefully placed and clamped inside. Another generous application of Abhesive 15-B was brushed on to the interior of the flexible mold so that the casting resin would eventually release from the mold.
The casting was made using Woodcast™, a pourable, lightweight, epoxy casting resin. It captures all of the detail of the original piece and is durable enough to be used for exterior applications. A modified version of WoodEpox® was also used in areas that required a non-slumping casting material. Fiberglass reinforcement was used with both casting compounds. The support mold was rotated during the process of pouring the resin, allowing enough time for the Woodcast to begin setting up before turning the support mold and pouring the next section.
The casting being revealed.
The end result was nothing short of amazing.
The completed replica is hollow and weighs approximately 45 pounds, but is durable enough to withstand the exterior elements. For questions on the moldmaking and casting process, or to receive a quote for your own project, please contact Abatron, Inc. at 800-445-1754.