Fixing the Cold Spots: Why Your Oven Needs Infrared
Ever pull a batch of parts out of a convection oven only to find some areas are perfectly cured while others are still tacky? It’s frustrating. You end up tossing a huge chunk of your product in the scrap bin just because the air didn’t quite reach every nook and cranny. That’s where infrared (IR) heat tubes come in. Instead of just relying on fans to push hot air around, we add IR tubes to the mix. It creates a sort of thermal balance that air alone just can’t touch. The secret is in how the heat moves. Convection is all about moving air, but IR is radiant energy. Think of it like the sun on your skin. By adding these tubes, we can hit the product surface directly. You don’t have to pray that a breeze carries the heat into a tight corner; you just get a consistent “blanket” of warmth. It closes the gap between your hottest and coldest spots. Picking the right gear You’ve got to think about your power supply here. High-wattage quartz tubes hit hard and fast, but they’ll pull a lot of juice. If you go with a high-density setup, your controls need to be snappy. If they’re too slow, you’ll overshoot your temperature and end up with a mess. We stick with high-purity quartz so the tubes don’t get cloudy or wear out after a few hundred cycles. The real-world trade-offs We use standard R7s or Sk15 connectors. Why? Because tubes eventually burn out. When that happens, you want to be able to pop a new one in and get back to work in minutes, not hours. But here’s the catch: IR is intense. If your parts are thin or sensitive, you might scorch the surface before the inside even gets warm. It’s a balancing act. You have to dial in the IR intensity against the airflow so the heat soaks in without burning the outside. Plus, you’ve got to get the spacing right. If the tubes are too far apart, you’ll see “tiger striping”—those annoying hot bands across your workpiece. Get the balance right, and you stop worrying about scrap rates.