Getting the Heat Right: Silkscreening and Tempering
When you try to combine silkscreen printing with tempering, you’re basically fighting a war with heat. It’s a tricky balance. On one hand, you need the ink to cure perfectly—no blurring, no burning. On the other, the glass itself has to hit that critical temperature to temper properly without creating internal stress. If you miss the mark on either side, you’ve got a problem. To hit that sweet spot, we use custom quartz infrared lamps. The battle against ink bleed Here is the thing about ink: if the surface of the glass stays too hot for too long, the ink viscosity drops. That’s when your crisp patterns start to blur. To stop that, we pick very specific wavebands for our lamps. We use shortwave IR because it punches through the surface quickly, driving the heat deep into the glass where it belongs. We fine-tune the wattage and voltage so the glass moves through the line fast, but the ink stays sharp. Why quartz matters We stick with high-purity quartz tubes for a simple reason: they can take a beating. In an integrated line, lamps are constantly ramping up and down. Cheap materials would just crack under that kind of stress. Plus, quartz is incredibly transparent. The infrared energy goes straight to the glass instead of wasting power heating up the lamp housing. It’s just more efficient. Speed vs. Stress It’s tempting to just crank up the power to get more glass through the door. But there’s a catch. If you push too much heat onto the surface, you risk “roller wave” distortion or uneven tempering. It ruins the strength of the glass. You have to play with the lamp spacing and the conveyor speed until it feels right. If you push the wattage too hard just to save a few seconds, you’re asking for trouble. Getting it running The best part? These heaters are drop-in replacements. You don’t need to rebuild your whole line. Just wire them into your controllers, calibrate your zones, and you’re good to go. One quick tip: don’t skimp on the ventilation. These lamps put out a massive amount of energy. If your cooling fans aren’t up to the task, you’ll end up melting your electrical connectors. And nobody wants that.