Glass Furnace Rebuild 2026
A Furnace’s Final Glow: After 25 Years, a New Era for Hot Glass at the Sandwich Glass Museum
by Scott Floeck
November 2025
After a quarter-century of near-constant use, the Sandwich Glass Museum is preparing to say goodbye to a true workhorse: our original glass furnace. Installed in the 1990s and run continuously (yes, 24 hours a day, 7 days a week), this furnace has powered countless live glassblowing demonstrations for our visitors and supported the museum’s mission of preserving and showcasing the art and science of glassmaking. Now, after 25 years of service, it’s time for a much-deserved retirement — and an upgrade.
Why Do Glass Furnaces Run 24/7?
Unlike a household oven, a glass furnace can’t simply be turned off at the end of the day. These furnaces operate at temperatures over 2,000°F, keeping glass in a molten state for shaping and working. Shutting one down isn’t just inconvenient — it’s risky and expensive.
Once cooled, the molten glass inside solidifies, and reheating it takes days or even weeks. Worse, the repeated heating and cooling can cause cracks in the furnace lining, reducing its lifespan or even making it unsafe to use. So for safety, longevity, and consistent glass quality, glass furnaces are designed to run non-stop.
Out with the Old, In with the HUB
Our new furnace, a HUB freestanding crucible furnace, represents a leap forward in both efficiency and maintainability. These furnaces are known for:
- 30–40% improved energy efficiency compared to older “day tank” furnaces
- A front-opening design that allows for easier crucible changes and interior maintenance
- A rugged interior made of high-alumina cast material, backed by 10 inches of fiber insulation to hold heat longer and reduce energy use
Despite their heavy-duty construction, HUB furnaces actually operate more quietly and use smaller burners, thanks to their efficient insulation. And they’re built to last — the manufacturer has been producing these furnaces for over 40 years, and all are reportedly still in operation.
A Safe and Smart Setup
Along with energy efficiency, safety is paramount. The new furnace will be equipped with modern automated controls, emergency shutoffs, gas leak detection, and proper ventilation. Operators wear full personal protective equipment (PPE) and follow strict protocols to ensure every demonstration is both safe and educational for the public.
Looking Ahead
The installation of our new furnace marks the beginning of an exciting chapter for the Sandwich Glass Museum. With better energy performance, lower operating costs, and improved maintenance access, we’ll be able to continue our live demonstrations — the heart of our visitor experience — for decades to come.
The transition will take place while the museum is closed during the month of January. The new furnace will be installed and tested during this time, and will be up and running again when we reopen in February 2026.
So the next time you visit and see molten glass glowing in the glory hole, know that behind the scenes is a state-of-the-art furnace, carrying forward the legacy of Sandwich glassmaking with strength, safety, and enduring heat.
