Today I was part of a Northeast Florida Sculptors outing to Pedroni’s Cast Stone facility.
We often go on these kind of field trips to check out artists studios or services that support the sculptural artist. Today was the latter. Craig Pedroni, President, gave us a personal tour of his place and explained a lot about the development of concrete over the years and especially how new techniques and materials can support a sculptor’s efforts.
Craig’s family has been involved in sculpting in Jacksonville since the 1920’s when his grandfather Andrew Frank Pedroni was a sculptor in Jacksonville. After World War II, Andrew Frank and his sons started an ornamental cast stone works in town. Craig then got involved in the 1970’s.
They are focused on custom, ornamental work, starting from the original art through, molding, casting and finishing. They make some pretty big pieces and need to have some heavy duty equipment to handle all of it.
We walked in the yard and saw some example pieces as he explained the process to us.
Once in the fabrication area we got more detail on the molding process and how it has evolved over the years from wooden boxes with the mold to the use of urethane and silicone molding materials to the use of intricately cut Styrofoam.
Artwork and a urethane mold, with lots of detail.
Newer molds can be made from artwork that’s been created on a CNC controlled router and the cast.
The use of these detailed molds and the additives used in the concrete provide casting detail not available in the past.
Some of the molds are made by casting Styrofoam pieces and Craig has a heavy-duty machine to deal with cutting the styrofoam. He has a large, hot wire CNC Styrofoam cutting machine that is capable of cutting Styrofoam into intricate shapes in Styrofoam blocks up to 8 feet thick! He ran a little demo for us.
Here’s the end result of this small demo.
Of course, both the Styrofoam for the molds and the concrete used are special purpose materials for the art world. The Styrofoam is much denser that normal Styrofoam with smaller beads. The concrete, all made to ASTM standards, has critical control of particle size and Craig has developed a great sense for the formulas that work best for each casting need. It.s not all about concrete either, since Craig is able to cast resins as well. He showed us an example of a cross made from resin that contained bronze powder to give a feel of metal in the finished product as well and a concrete insert to add weight to the casting.
Craig ended the tour by making a sample batch of concrete. Since concrete strength is improved by adding less water into the mix, he created a very stiff mix to start. Although strong, this material can’t effectively cast details, but like magic he added some “modifier” that made the concrete become almost liquid, but added to water allowing him to cast without a problem.
There were nearly forty of us there today and I know all of us really enjoyed the facility tour.