How We Made a 30CM Lady Justice Silicone Mold

This project documents the real G6003 workshop process for a large Lady Justice bust mold. The mold combines a flexible silicone inner layer with a rigid sectional support shell. The finished casting shown is approximately 30 × 20.3 × 19.7 cm.

The steps follow the supplied video: bottom-edge sealing, a small first pour, a second pour about 40 minutes later, demolding after about 4 hours, trimming, plaster casting and final demolding. Those timings describe this recorded run rather than a universal cure schedule.

Video: https://www.youtube.com/watch?v=sXyhn0autC4

Workshop article: https://www.bksilicone.com/how-30cm-lady-justice-silicone-mold-uses-support-shell-g6003/

Product page: https://www.bksilicone.com/30cm-lady-justice-bust-silicone-mold-with-support-shell-g6003/

Shopify: https://shop.bksilicone.com/products/30cm-lady-justice-bust-silicone-mold-with-support-shell-for-plaster-resin-concrete-casting

Materials: Lady Justice master used for this G6003 workshop run; silicone used to form the flexible inner mold; rigid sectional support shell; double-sided tape; binder clips; plaster for the casting test.

Tools: mixing and pouring containers; trimming tool; basic assembly tools shown in the workshop video.

Check that the Lady Justice master sits correctly inside the sectional support system. The outer shell must close around the mold while remaining removable for demolding.

Apply double-sided tape along the bottom edge. The goal is to establish a practical seal before liquid silicone creates pressure at the base.

Join the rigid shell sections with binder clips. The clips hold alignment during pouring and can be removed when it is time to open the mold.

Start with a small silicone batch. A low initial liquid level reduces pressure at the bottom and allows the seal to be checked before more material is added.

About 40 minutes later in this recorded G6003 run, add the remaining silicone to complete the inner mold. This is project evidence, not a universal timing rule.

The workshop video returns about 4 hours later, when the silicone is fully cured for this run. Check the instructions for any different silicone system.

Remove the clips and separate the rigid shell sections carefully so the cured silicone inner mold and the master are not damaged.

Separate the flexible silicone mold and inspect the Lady Justice detail. The silicone holds the sculptural surface while the outer shell provides structural support.

Trim excess silicone around the opening and edges. A clean opening makes reassembly and casting easier.

Reassemble the silicone inner mold inside the support shell, secure the sections, and fill with plaster. No special plaster formula is claimed; this is a practical system test.

Open the support shell and peel back the silicone carefully. Inspect the finished Lady Justice casting for overall shape and reproduced detail.