Clear quartz infrared tube

Fri, 24 Jul 2026 10:40:58 +0800

Fixing Those Pesky Cold Spots in Complex Glass Annealing

Ever deal with “cold spots” when annealing a tricky piece of glassware? It’s frustrating. You’ve got these weird geometries that basically act like shields, blocking the heat and leaving internal stresses in the glass. Standard convection ovens just can’t reach those hidden nooks. That’s why we use clear quartz infrared (IR) tubes. Instead of hoping the hot air drifts into the right place, we just push the heat directly into those recessed areas using radiation. How the heat actually gets there Here’s the thing about clear quartz: it lets short-wave IR radiation slide right through the tube wall without soaking it up. While coated tubes tend to bounce heat back, clear ones send out a focused beam. If you set these tubes up in multi-angle arrays around your piece, you’re hitting the glass from every possible direction. It fills in all those gaps where air-based heating usually gives up. The gear and the grit We stick with high-purity fused quartz because it can take a beating at the extreme temperatures annealing requires. It stays strong and clear even when you’re pushing it to the limit. But a heads-up: this stuff is fragile. If your shop has a lot of vibration, don’t just bolt them in. Use a dampened mounting bracket. Trust me, you don’t want to find a crack in your quartz halfway through a run. Setting up your layout Don’t make the mistake of relying on one single heat source. It won’t work. Instead, try a staggered setup. Layer your tubes at different heights and angles to create a volumetric heat zone. It basically wraps your workpiece in a warm blanket of IR energy. One more thing—keep an eye on your wattage. High-wattage tubes put out a lot of intense heat. If you crank up the power but your kiln’s ventilation is lacking, you’re going to fry the tube ends and burn out your connectors. And for heaven’s sake, use high-temperature leads. You really don’t want your insulation melting right next to the quartz seals.

Clear on Warm IR Heater Connection

Clear quartz infrared tube

Fixing Those Pesky Cold Spots in Complex Glass Annealing