Overview
Form S71 is an Opacity Chart of the LENETA brand, model number Form S71. The product is black and white lame plating strips, black on the left and white on the right, with an overall size of 2 x 11 inches (51 x 279 mm). It is mainly used to evaluate hiding power of spray-on lining, especially in the automotive industry (including tinkering operations). When used, cardboard is usually attached to a steel plate or Aluminum Panel, and lame plating tests the coating to form a "wedge" with a gradual change in thickness. After drying, by determining the position on the cardboard to achieve a sufficient visual covering (usually a contrast ratio of 0.98), and measurement of the coating film thickness at this position on the adjacent metal plate, or vice versa, measurement contrast ratio near the specified film thickness position, to evaluate the covering performance of the coating.
Features
1. Designed for evaluating spray-on lining hiding power, especially for the automotive industry.
2. Adopt a classic design with black bars and white bars symmetrical left and right, which is convenient for comparison and observation.
3. The standard size is 51 x 279 mm (2 x 11 inches), making it easy to use with metal test plates.
4. Encasement size is 500 sheets/box, each box weighs about 5 pounds, easy to use and store in batches.
Principle
The Opacity Chart provides a contrasting background for evaluating the hiding power of the paint through its left-right symmetrical black and white areas. When testing, the cardboard is attached to a metal substrate (such as a steel plate or Aluminum Panel), and then lame plated to form a wedge-shaped coating that is thin at one end and thick at the other. After the coating is dried, the operator looks at the black and white areas on the cardboard to find where the coating just happens to completely cover the underlying base color (i.e. achieve a specific visual contrast ratio, such as 0.98). By measuring the coating wet-film or dry-film thickness corresponding to this position on the metal substrate, the film thickness required for the coating to achieve complete coverage can be quantified to evaluate its coverage efficiency. Conversely, the contrast ratio can also be measured at the specified film thickness.
Applications
Evaluation of spray-on-lining hiding power in the automotive industry (including repair operations)
Steps
Attach the Form S71 Opacity Chart firmly to a metal test plate such as a steel plate or Aluminum Panel.
2. On top of the cardboard and some metal plates, lame plating the coating to be tested, forming a "wedge-shaped" film layer with thin coating at one end and thick coating at the other end.
3. Wait for the test coating to dry through.
4. Observe the dried cardboard and determine the exact location where the black or white stripes are fully covered by the coating and achieve a predetermined visual contrast ratio (e.g. 0.98).
5. Measurement of the film thickness of the coating on the metal plate area adjacent to this location. Alternatively, determine the location of the specified thickness on the metal plate first, and then measure the contrast ratio of the coating on the cardboard near that location.
Notice
Before use, please ensure that the surface of the cardboard is clean and free of damage to ensure the accuracy of the test results.
• Ensure that a uniform, continuous wedge-shaped coating layer is formed during lame plating.
• Coatings must be observed and measured through drying.
• When measuring film thickness, ensure that the measurement point corresponds accurately to the covering critical point observed on the cardboard.
• This product is a test consumable, please use and store it reasonably according to the actual test requirements.
