Picking the Right IR Lamp for Alloy Wheels
If you’re curing powder coatings on alloy wheels, you know the struggle. You need a massive amount of heat to get that finish to bond, but if you overdo it or heat it the wrong way, you risk warping the whole wheel. That’s why we stick with shortwave infrared (SWIR) lamps. Instead of wasting time heating up all the air in the oven, these lamps shoot energy straight into the coating. It’s a lot more efficient. Getting the heat right The goal here is to hit peak temperature fast. To do that, we usually go with high-wattage tubes packed into a short length. It creates a concentrated blast of heat. For example, sticking a 2500W tube in a compact oven gives you that rapid ramp-up you need for a rock-hard cure. Just a heads-up: make sure your wiring and power supply can actually take the hit. Those high-wattage tubes put a lot of stress on your contactors, and nobody wants a blown fuse in the middle of a shift. The gear that makes it work We use high-purity quartz glass because it can handle the shock of heating up and cooling down rapidly without snapping. To make things even faster, we often use gold-coated or aluminized reflectors. They basically bounce the energy right back onto the rim, which stops heat from leaking out and shaves time off your cycle. We also keep things simple with standard R7s or Sk15 connectors. When a lamp eventually burns out, you just swap it and keep moving. No need to spend an hour rewiring the whole rig. A few things to watch out for Shortwave lamps are fast, but they’re a bit finicky. Here is the annoying part: you cannot touch the quartz tubes with your bare hands. A single fingerprint can create a hot spot, and the glass will crack the first time you fire it up. Always use gloves. Then there’s “skinning.” Because SWIR works so quickly, it can cure the surface before the solvents underneath have a chance to escape. If that happens, you’ll end up with tiny pinholes in your finish. You’ll have to play around with your conveyor speed and temperature zones until you find that sweet spot.