A visiting artist engagement at Ramapo College of New Jersey, where Joel Weissman runs the sculpture program. Joel is a good friend and cast metal artist who has been following the WVO research closely.

Short version: this thing has never run cleaner or hotter.

First tap took about 25–30 minutes to build, then they got faster and faster as the campaign progressed. By the end we were pulling 100 lbs every 12–13 minutes — about twice the speed of our previous best. Metal was boiling hot. Highest temperature we've observed.

The nozzle extension — extended to within 2.5" of the inner well wall — worked exactly as hoped. No oil in the well. No flames flickering around the bottom door. Two recurring problems since the beginning, both gone. The furnace was running in a balanced, slightly lean combustion environment — clean flame, no smoke, no drama.

The remaining problem is carbon content. With oil pyrolysis in the well now eliminated, excess oxygen in the blast appears to be burning out carbon before it can saturate the iron. The next test at Union College will run a purely reducing atmosphere with powdered graphite added to the ladle inoculation — direct carbon addition at the point of tapping, bypassing the combustion environment.

This summer we visited East Germany to help artist Hans Molzberger at Hilmsen Atelier convert his large tilt furnace into a state-of-the-art waste oil iron caster — a full conversion from a legacy coke system to a WVO-fired operation capable of matching its predecessor's output.

Stack removal, custom grate fabrication to fit the existing furnace geometry at Hilmsen Atelier, and installation of the burner port. The tilt furnace presented unique structural challenges compared to our fixed cupolette — the burner mount had to accommodate the tilt axis while maintaining consistent flame geometry across the full range of motion.

The burner was designed and built entirely on site, fabricated to match the specific dimensions and airflow requirements of the Molzberger furnace. Highly adjustable — fuel rate, air ratio, and flame angle all independently tunable. This level of adjustability proved essential during the tuning process, where small changes in air-to-fuel ratio produced significantly different combustion characters.

Grates were cured in place, the furnace fully assembled, and the first test fire conducted. Iron was produced. The conversion is operational.

The fall 2024 campaign at Salem Art Works marked a significant turning point in the research — the first heat with the compressed air burner upgrade, replacing the original PWP burner system. The results were immediate and dramatic.

Melt rate more than doubled compared to the December 2023 baseline — from ~163 lbs/hr to ~375 lbs/hr. The upgraded blower was sized to match the compressed air burner's blast CFM, and the furnace responded. Tap intervals settled at 20–21 minutes and held consistently through the campaign.

Feedstock was primarily radiators transitioning to rotors — the first time brake rotor scrap was introduced in volume. Fuel consumption was approximately 22 gallons of WVO over the campaign at around 7 GPH — the efficiency baseline that subsequent heats have been measured against.

The melt rate gains overshadowed a quality issue that would become the central focus of later work: moderate fluidity loss was present throughout, with metal developing a slushy, pudding-like character in the ladle rather than pouring with the clean, fluid behavior of well-saturated gray iron. At the time this was attributed to ladle cooling. Subsequent analysis identified the real cause — progressive carbon loss from an oxidizing combustion environment — but the SAW heat was where the symptom first appeared clearly enough to track.

The compressed air burner has been the production system for every campaign since. Salem Art Works established it as the right platform to build on.

A week-long visiting artist engagement at Auburn University in March 2024, hosted by Kristen Tordella-Williams and the Auburn sculpture program. The visit centered on designing, fabricating, and firing a prototype WVO biofoundry furnace — a sister build to the FMS cupolette — on site at Auburn's facilities.

The week included a full artist lecture drawing on the sustainable foundry research and Jeremy's broader sculptural practice, and culminated in a pop-up exhibition. Auburn became the first institution outside of FMS to build and operate a version of the WVO furnace, establishing the research as a transferable, replicable system rather than a single-studio experiment.

The Auburn furnace was fabricated from scratch during the residency week, using the refined FMS cupolette geometry as the design basis. Burner configuration, well dimensions, and grate design were all adapted to Auburn's available materials and facilities. The furnace was fired and producing heat by the end of the week — proof that the system could be built and operated by a new team in a new location with no specialized infrastructure.

The WVO cupolette program began at French Mountain Studios in Lake George, NY — years of design, fabrication, and testing before the first successful iron heat. The core challenge: replicating the thermal environment of a coke-fired cupola using a liquid fuel system, without the fuel handling complexity of propane or the carbon footprint of diesel.

Early heats established the fundamental burner geometry and well configuration that all subsequent furnaces have built on. The first successful 100 lb tap of iron — WVO-fired, no coke, no propane — marked the proof of concept. Every campaign since has been refinement.

Video documentation of early taps available below.