Loodgieten van contramassa's
Some years ago I was working on a nice large balanced sculpture with floating pyramids of stainless steel (see blogs here, here and here), but due to the covid-cancellation of the exhibition the sculpture remained unfinished. On Friday I made another step with the sculpture by lead casting of the two counter-masses of 32 kg each, for which I asked the help of Emile Luijben alias Mastermilo.
The counter-masses are 20 mm thick trapezium shaped plates for which I made a mold of steel. I placed two copper tubes along the middle of the plate to create holes in the plate such that it can be placed on rods. Then the plate can slide along the rods for fine-tuning of the balance of the sculpture, for which in the center of the mold I included a screw-nut.
I collected 100 kg of old lead and wood from pallets for the fire. Then I went to Emile and his friends and in his workshop we made the setup for the casting and melting of the lead. First we made a crucible from an old gas tank. Of course everything was filmed for his youtube channel.
In the meantime the fire was prepared outside, using oil barrels for the wood fire. It was impressive to see how quickly 50 kg of lead was molten, the heat of the wood fire made the lead easily reach its melting point of 327 °C.
After a first failure, the two plates of lead turned out quite nicely. We had some difficulties with the steel mold which deformed much more than expected due to the heat of the lead. That was interesting to learn.
You can watch the complete lead casting process in this video of Emile: