This standard is issued under the fixed designation D ; the number 1 This practice is under the jurisdiction of ASTM Committee D01 on Paint and. Related. Wet film thickness is measured according to ASTM D, Standard Practice for Measurement of Wet Film Thickness by Notch Gages. Pictures. The methods for measuring surface profile are described in ASTM D, . Wet film thickness is measured in accordance with ASTM D
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Standard ASTM D The following devices are in accordance with ASTM D ZMK - Road Marking Control Kits. Specially designed for road . You can download and read online PDF Astm D Book file only if you us: epub, ebook, kindle, paperbook, and another formats. Here is. Standard test methods are available in ASTM D, ISO and . ASTM D outlines a standard method for this measurement. Powder.
Scope 2. There are ments additional techniques suitable for laboratory use not covered by 3. Summary of Test Method these test methods. The values given in parentheses are for information the blast cleaned surface forming a reverse image of the profile, only.
It is the tape method.
Significance and Use mine the applicability of regulatory limitations prior to use. Referenced Documents For this reason, surface profile should be measured prior to coating application to ensure that it meets that specified. The 2. Profile depth designations E Practice for Use of the Terms Precision and Bias in are based on the concept of mean maximum profile h max ; this value is ASTM Test Methods determined by averaging a given number usually 20 of the highest peak E Practice for Conducting an Interlaboratory Study to to lowest valley measurements made in the field of view of a standard Determine the Precision of a Test Method measuring microscope.
This is done because of evidence that coatings performance in any one small area is primarily influenced by the highest surface features in that area and not by the average roughness. Current edition approved Jan. Published March Originally of areas each approximately one square inch in size , usually approved in Last previous edition approved in as D DOI: 3 Keane, Joseph A.
Bruno, Jr. Fifth Ave. No further reproductions authorized. D 14 1 The tape consists of a compressible foam coated onto an incompressible polyester substrate.
Procedure Each area is marked giving the nominal profile depth in mils or 7. Typical comparator surfaces are prepared with 7. The comparator areas are used with or without to be measured and compare the roughness of the prepared magnification of 5 to 10 power.
This 5. The probe is typically machined at a 60 included angle magnification, or by touch.
When using magnification, the with a nominal radius of 50 m and exerting a minimum force magnifier should be brought into intimate contact with the of 75 g. The base of the instrument rests on the tops of the standard, and the depth of focus must be sufficient for the peaks of the surface profile while the spring loaded tip projects standard and surface to be in focus simultaneously.
For a given side, the two outside teeth or notches are the same size and are actually a zero reference datum which represents the substrate. All the other teeth or notches on the same side are of shorter lengths than the outside teeth or notches and represent different distances from the outside edge zero datum teeth.
These different distances represent the surface of the wet coating thickness to be measured. The teeth or notches are graduated in MILS 0. See drawing below.
Instructions On How To Use A 'Wet Film Thickness Gauge' Place the wet film thickness gauge at ninety degrees to the coated substrate and penetrate the surface of the coating with the notched or toothed side of the gauge until the substrate is firmly contacted.
Wait several seconds to allow the teeth or notches of the gauge to become 'wetted' by the coating, then withdraw the gauge vertically keeping it at ninety degrees to the substrate. The gauge may now be read to determine the wet film thickness. The ends of the teeth or notches are visually examined, some will be coated or 'wet' and some will not be coated or 'wet'. The wet film thickness WFT of the coating lies between the values of the smallest un-coated dry tooth or notch and the largest coated wet tooth or notch.
Be sure to clean the gauge with an appropriate solvent after use. When wet film thickness is measured with the gauges on rough substrates, the thickness measurements made will most likely be from the surface 'peaks' and the wet film thickness measurement will represent the minimum overall wet film thickness.
On curved surfaces such as pipes, cylinders, etc. If quick drying coatings are to be measured, quickly perform your measurements to avoid errors that may be caused by curing.
Measuring Powder Coatings The thickness of dry powder coatings may also be measured with these type of gauges.