Mold Making and Our Process
April 27, 2023
Mold Making is a multi-step process that includes many different materials, especially depending on what the end cast’s material is composed of. Let’s start from the beginning, your piece.
At Cherrylion studios the first step is our clients and their desired sculptures. Big or small Cherrylion has made a wide variety of work come to life. After an idea is presented to Martin Dawe, the owner and sculptor here at Cherrylion Studios, then a maquette is created to show the client a visual of their idea. Maquettes are just a small version of the proposed sculpture that will represent the dimensions in a visual way. This common practice helps to work out any uncertainties in communication between artists and their clients. After approval, the desired size piece is sculpted from clay and approved again between artist Martin Dawe and client.
The sculptures final material will determine how the mold is constructed, but as a base line for Cherrylion Studios, rubber and plaster are most always used. For example, when a sculpture is molded with the intent for it to be made of bronze or resin, the rubber and plaster method is used for its’ mold. We work with a foundry called Art City Bronze for all our bronze casting, but in house we utilize resin and metal powder to create resin bronze sculptures.
To begin the mold making process, the sculpture is studied to account for possible undercuts and for how the mold will be segmented. This is an extremely important process due to the undercuts; these can cause the mold to lock up around the sculpture making it impossible to remove. To minimize damage to the original sculpture, each of our molds are graphed out into sections and wax or spray release is applied for ease of removal.
After the spray release has been applied to the entire sculpture, the first coat of rubber is introduced. This coat is a very thin and runny coat to ensure all of the details are picked up in the sculpture. Depending how large or small the sculpture is, we may have to do this step again to ensure a very thin layer covers the entire piece. Then the next layers that are added are mixed with thickener to expedite the process while making it easier to coat the sculpture in rubber. Before the final few layers are introduced, bumper walls or shims are added to create the segmented pieces for demolding. Then one final thin coat of rubber is used to smooth out any odd textures and unify everything together.
“Why do we need plaster for a rubber mold?” is equivalent to asking why people need bones, something has to keep the rubbers’ shape during the mold making process, or the whole thing will just collapse. After the rubber is completely cured, it is coated in wax and the plaster splash coat is applied; this coat, like the first rubber coat, is thin too. The purpose for this coat is to create a smooth layer of plaster that will lay against the rubber. The next couple layers have burlap trimmings coated in the plaster to strengthen the mother mold. Remember the shim and bumper walls we made during the rubber phase? This is our guide for the mother molds’ shape and how they will be drilled together for casting.
Once the Mother mold is cured and drilled out, the sections of plaster can start being removed. The rubber has to be cut along the seams of where the bumpers or shim walls were made. These inner and outer layer pieces are numbered for the convenience of reassembly.
Especially if the sculpture is larger, once the mold is deconstructed into many different pieces it can be difficult putting them all back together correctly. The pieces of the rubber are washed and dried, the plaster is scrapped smooth and torched to get rid of any burlap that’s sticking out of the plaster. Now the mold is ready for casting.
If the sculpture is a bronze piece, we build a crate and ship it to Art City Bronze in Utah; if the sculpture is a resin piece, we cast it here at Cherrylion Studios. Either process chosen will always result in a bit of clean up after casting. This is where the expert mold makers ensure seam lines are minimized and the connection points are undetectable. Mold making is a versatile process that can get you amazing sculptures with immaculate detail.
If you are looking to get a sculpture fabricated or have a piece you made be cast in bronze or resin, contact Cherrylion today for a consultation!
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