How Infrared Curing Lamps Work

Introduction to Infrared Curing Lamps in Bodyshops

An infrared curing lamp is usually a set of heating elements on a stand or a rail, aimed at a freshly filled or painted area of a car. It gives off infrared energy that warms the coating and the surface underneath. With products made for force drying, that heat lets filler or primer reach the next stage sooner than it would at room temperature.

Typical uses are small areas, such as a spot repair or a single panel, and filler or primer that has to be sanded before the next coat goes on. This guide explains how the lamps work in general terms. It does not describe the equipment at Coventry Body Shop, where all paintwork is sprayed in our spray booth.

The Science Behind Infrared Curing

Infrared is the part of the electromagnetic spectrum just beyond visible red light. When it strikes a surface, part of it is absorbed and turned into heat. A convection heater warms the air first, and the air then warms the panel. An infrared lamp sends its energy straight at the surface it faces, so less of the heat goes into the air first.

Lamp makers sort their elements into short-wave, medium-wave and long-wave types, and each type warms up and heats a coating in its own way. How much energy a coating takes in also depends on its colour and pigments. Two panels under the same lamp can therefore reach different temperatures, which is why some lamps read the surface temperature as they work.

Benefits of Infrared Curing Lamps in Automotive Repairs

• Shorter waits: where the product allows force drying, filler and primer can be sanded sooner, and a lacquered spot repair can be handled sooner than if it were left to air dry.
• Local heat: the heat goes mostly into the area the lamp faces, so one panel can be cured without warming the whole car. Trim and seals close to the repair can still get warm.

Parts of a curved panel sit further from the lamp than others and can heat unevenly, and the elements need careful aiming near glass and rubber seals.

Application in Paint Correction and Colour Matching

A lamp does not change how a colour is matched. At Coventry Body Shop every colour starts from the manufacturer's paint code and specialist colour mixing, we can read the existing paint with a spectrophotometer, and the new colour is blended where the repair needs it.

Fresh lacquer can still be soft after it is touch dry, and machine polishing it too early can leave marks or dull the gloss. Many lacquer data sheets give a wait before polishing, and some give a shorter wait after force drying. New paint from a SMART repair needs its curing time like any other paint. Polishing older, fully hardened paint, as in scratch removal and machine polish, does not involve curing new paint.

Infrared Curing in Accident Repair

Accident repairs build up in layers. On a dent repair and respray, the panel is straightened, then filled and primed where needed before the colour and lacquer go on. Each layer needs its flash-off or cure time before the next step. Filler is sanded, and so is primer in many repairs. Sanding a layer that is still soft clogs the paper and leaves a poor surface.

In bodyshops that use them, lamps can shorten the waits between layers. For a product that can be force dried, the paint maker's technical data sheet normally sets out the conditions, and the lamp maker's instructions cover distance and settings. The two have to agree, and a product without a force-drying procedure is left to dry as its data sheet says. Heating a coat before its flash-off has finished can trap solvent, which is one cause of the small blisters or pinholes painters call solvent pop.

Quality Control and Longevity Considerations

Under-curing and over-curing can both shorten the life of a repair. A film that has not fully hardened can stay soft and take marks from washing or polishing, and it can lose gloss as the last of the solvent leaves it. Too much heat, from a lamp set too close or left on too long, can blister or wrinkle the paint.

Plastic bumpers can distort at temperatures that a steel wing takes without harm, and parking sensors and seals close by can be damaged by stray heat. Plastic is one reason a bumper repair is handled differently from work on a steel panel.

Preparation and the thickness of each coat also affect how long paint lasts, whichever way the paint is dried.

Choosing the Right Infrared Curing Equipment

Portable lamps on wheeled stands are usually used for spot repairs and single panels, since they can be moved around the car and angled to the panel. Rail-mounted systems run along a booth or a prep bay and can cover larger areas. Buyers also compare the size of the heated area, the type of element, the timer and whether the lamp reads the surface temperature.

Conclusion: The Future of Infrared Curing in Bodyshops

Infrared lamps shorten curing times on small areas and on filler and primer, provided the product can be force dried and the lamp is set to match its data sheet. Heat-sensitive parts near the repair need protecting while the lamp is on.

At Coventry Body Shop, all paintwork is sprayed in our spray booth, to the paint maker's and the vehicle maker's methods, and we give a written, itemised estimate before any work starts. To get one, send photos by WhatsApp or through the Send enquiry button.

The repairs we quote for include a SMART repair, scratch removal and machine polish, panel dent repair and respray, bumper repair and a full body respray, which usually takes 3 to 7 days, depending on what the car needs. Our workmanship guarantee runs for up to 6 months from collection.