Materials Testing

Over the past several years there has been a dramatic increase in demand for tinted headlight and taillight covers. Whether we are talking about a show car, a race car or even your daily driver, the demand is unmistakable. But this demand has brought a lot of shady vendors to the fore. Caveat emptor is certainly the word of the day. Before we added our line of colored lighting protection kits we bought kits from a wide variety of sources and put them through the tests to see how they lived up to their billing.

We bought from 'blindly paypal me the money' type people, a variety of ebay sticker people, and several online shops. What did we find? Not a single one came anywhere close to as was advertised! We used our tint meter (used to measure the light transmission and legality of window tints) to verify light transmission claims. We measured thickness with our caliper, and heat properties with a pyrometer. We tested durability and temperature stability from freezing cold to hotter than blazes Texas sun.

'Overlays' Every time we tested something that looked like what we were looking for and was advertised as an overlay, what we got was a piece of transparent sign making vinyl or window tint. 2-3mil thin and delicate. Everyday copy paper is 4mil for comparison. We pressed one person for the film thickness and each time he came back with 'it is 7 year vinyl' and no mention of its thinner than paper quality. When we received the order, the directions said 'dunk the kit is a bucket of soapy water and apply'... The overlays we tested were certainly a prime example of 'you got what you paid for', less really.

'Tints' We tested a few smoked kits marketed as 'Tints'. One was window tint designed for glass and impossible to get to lay down on our test headlight. One didn't even have adhesive, it was (not) held on by static cling. While we were able to apply it, it did blow off the first time we drove on the highway... Although very inexpensive, again it was a prime example of 'you got what you paid for', less really

Clear Bra Several sets of clear headlight protection kits we tested we nothing more than paint protection film - clear bra material cut in the shape of a headlight. While some of these did work, some didn't fit at all because paint protection film likes to be stretched, not compressed like you need to do to install some of the more complex headlight kits. In some cases it was simply impossible to install the material designed for paint protection in a lighting protection application.

Temperature Resistance Most materials tested did acceptable in temperature resistance as far as the temperatures expected in a lighting applications.

Headlight Armor Temperature Testing Results - 30 minutes sustained temperature - dry - minimal air flow

Lens Material Temp F Pass / Fail
Glass 225+ Pass
Acrylic / Plexiglas 180 Pass
Polycarbonate / Lexan 225+ Pass

HID Headlights typically run cooler on the front side than halogen bulbs. Think the difference between a fluorescent bulb in your office light vs a halogen one. This is one reason most European cars with factory HID's come with headlight washers. The lens does not get hot enough to keep ice from building up on them when driving in the snow.

Polycarbonate and Lexan, what most composite headlights are made from these days, have a continuous working temperature of between 248 - 475 F depending on the formulation, Plexiglas & acrylic, though not typically used for automotive headlights, both have a continuous working temperature of about 180 F. In either case I wouldn't want to touch a headlight lens that got that hot! In field testing we have never seen a headlight get anywhere near that hot. Keep in mind that if you want dark lights and brighter lights at the same time you are asking too much. Generally speaking, trying to make the lights brighter will introduce more additional light than additional heat. Trying to darken the lights by 'tinting' them, and then making up for the loss in output with different bulbs is asking for trouble.