Scratch Test

A vehicle cover’s most obvious role is to provide a barrier against the elements. From dust to UV rays, to rain, sleet, and snow, it is important that the user select a cover that will meet his or her specific needs. Yet it is the interior of that cover – often times a different material entirely – that actually comes in direct contact with the vehicle’s finish.

It follows therefore that a vehicle cover’s success in protecting against the elements is meaningless if it fails to protect the finish from unsightly scratches or micro-abrasions, which can dull a vehicle’s finish over time. These are both caused by friction, for which there are two main sources.

The primary source by far is strong sustained and gusting wind, which inevitably causes any cover to slide and flap against its vehicle. Of secondary concern is the friction generated during installation and removal of the car cover, although it must be pointed out that this friction can vary greatly from user to user.

To ensure that we offer the best products available, the EmpireCovers Research & Development Team conducts rigorous testing of our products before entering into commercial production. We, therefore, devised a Scratch Test that allows us to systematically quantify the effects that different car covers have on a vehicle’s finish.


We tested the interior cloth material of four different covers: the Indoor Basic Cover, Titan 4-Layer Series, Titan 5-Layer Series, and American Armor RipStop, with 150 grit sandpaper tested as a control.

Our method consisted of simulating friction between each of these materials and the surface of a vehicle, the goal being to recreate wear and tear. It should be noted, however, that these testing conditions were far more extreme than any user might reasonably expect to encounter. This was to ensure an observable, quantifiable result.

To guarantee uniformity across all tests, our engineering team custom-built a proprietary scratch testing device. To guarantee realism, they procured 18 gauge steel (roughly ½” thick) plates that mimicked the finish found on new vehicles. The plates procured were finished in flat black color since this color reveals maximum damage under a microscope.

For each test, a sample of the respective cover’s interior fabric was loaded onto the vibrating side of the scratch tester, with care taken to pull the cloth taut across the entire machine face. The cloth and a test plate were then pressed together at 45 lbs., and the cloth rotated at 14,000 RPM for a total of 8 seconds. Watch the video to the right to see our test in action.

This method was repeated for each material, with results photographed under 55X magnification. These results were then compared to control photographs, which were taken prior to any abrasion, also at 55X magnification.

Test Results

Sandpaper was included as the control in order to demonstrate a “worst case scenario,” and predictably caused considerable abrasion to the test plate.

Among all four covers tested, each was found to perform to a minimum of “good,” with one performing “very good,” and two others, “excellent.”

As noted above, these results were derived using extreme testing conditions. In fact, the pressure and RPM used in our testing exceed the wind speeds of an average tornado. Customers can, therefore, feel confident that these covers will cause virtually no damage, even in extreme weather conditions.

Excellent Performance

In our tests, the Titan 5-Layer Series and American Armor Ripstop both achieved an “excellent” rating, causing nearly imperceptible abrasion to the test plates. In addition to long-term wind, rain, and sun protection capabilities, American Armor RipStop Cover's micro-fiber lining actually polished the test plate finish in our testing.

Very Good Performance

The Titan 3-Layer Series was rated “very good” in our scratch tests, with faint to no abrasion caused to the test plates. These are both cross-functional covers with versatile capabilities. The Titan 3-Layer Series is a budget-conscious cover intended for occasional outdoor use in protection from the sun, dust, dirt, tree sap, pollutants, and water.

Good Performance

Titan 4-Layer Series and Indoor Basic Covers both performed in the “good” category, causing minimal abrasion to the test plates. Each is a budget-conscious cover designed for very specific uses. The Titan 4-Layer Series provides UV, dust, dirt, and pollutants while keeping the vehicle cool - useful features in climates such as deserts.

Learn more about how our covers protect against other harmful elements.

Learn More