DeFelsko PosiTest PG Paint Inspection Gage Instruction Manual
- September 20, 2024
- DeFelsko
Table of Contents
DeFelsko PosiTest PG Paint Inspection Gage
Introduction
The PosiTest PGPaint Inspection Gageis a precision instrument used to measure
the total coating thickness or individual layer thickness of coatings over any
rigid substrate, including metal, wood, and plastic.
The PosiTest PG uses a carbide cutting tip to cut a groove into the coating at
a specified angle. The groove is then observed under an illuminated
microscope, and coating thickness is determined using the scale markings on
the reticle.
Measuring Coating Thickness
-
Select a location to perform the measurement that is flat and level.
-
Make a mark approximately 50 mm (2”) long on the coating, using the included black marker, or another marker of a color contrasting to the surface.
-
Pull out the selection dial and turn it to select a cutting tip based on the expected coating thickness, using the chart below. If the coating thickness is unknown, perform an initial measurement using the 2X cutting tip.
Cutting Tip| Angle| Coating Thickness Range
---|---|---
Microns| Mils
1X| 45°| 0 – 1,250 µm| 0 – 50 mils
2X| 26.56°| 0 – 625 µm| 0 – 25 mils
5X*| 11.31°| 0 – 250 µm| 0 – 10 mils
10X| 5.71°| 0 – 125 µm| 0 – 5 mils -
Place the gage on the surface, such that the cutting tip and guide wheel are flat and level on the surface.
-
Pull the gage towards the operator, creating a perpendicular cut through the marked line. Apply just enough pressure to cut into the substrate.
-
Turn on the built-in light (pg. 3), and align the microscope over the intersection of the mark and groove cut.
-
Observe the cut through the eyepiece, focusing the micro-scope using the focusing wheel and rotating the eyepiece as necessary to properly align the reticle markings with the groove.
NOTE : When measuring, it is often beneficial to line up one of the major graduation marks with the edge of the coating. It is not necessary to align with the zero mark on the scale. Measurement (1x Cutting Tip) = 0.76mm / 760µm / 0.03” / 30 mils
(2x Cutting Tip) = 0.38mm / 380µm / 0.015” / 15mils
(10x Cutting Tip) = 0.076 mm / 76 µm / 0.003” / 3 mils -
Record the width of the cut, measuring from the edge of the substrate to the edge of the contrasting mark, by counting the number of graduations. If measuring a multilayer coating system, the width of each individual layer may be recorded.
NOTE : Measurements in mils/inches should use the graduation marks above the center line. Measurements in microns/millimeters should use the graduation marks below the center line. -
Multiply the measured width of the cut by the conversion factor from the table below to determine the coating thickness.
Conversion Chart
| Cutting Tip | Conversion Factor | Each Graduation Measures |
|---|---|---|
| Microns | Mils | |
| 1X | 1 | 20 |
| 2X | 0.5 | 10 |
| 5X | 0.2 | 4 |
| 10X | 0.1 | 2 |
Built-in Microscope Light
The built-in light illuminates the measurement area to assist with optical
inspection.
The light can be toggled on/off by pressing the button on the front of the
gage. The light will automatically power off after 5 minutes.
The light is powered by 1 AAA battery. It is oriented with the positive
terminal facing down, inside the battery compartment.
Adjusting and Replacing Cutting Tips
The PosiTestPGfeatures 4 cutting tip holders and a selection dial, with
positions marked for the 1X, 2X, and 10X cutting tips. The fourth holder can
be used for an optional cutting tip, or left empty for storing the gage.
To rotate the cutting tip holder, pull out the selection dial and turn to the
desired position. Release the selection dial, ensuring that the tip is locked
into place.
Replacing Cutting Tips
- Rotate the cutting tip holder into position.
- Loosen the hex screw at the base of the cutting tip using the included 1/8” hex wrench.
- Remove the cutting tip.
- Install a new cutting tip such that the tallest part of the cutting tip is closer to the selection dial. Ensure that the cutting tip is seated fully into the cutting tip holder.
- Retighten the hex screw until the cutting tip is firmly held in place.
Troubleshooting
Oil, dust, or other obstructions can be removed from the microscope lens by
gently cleaning with a cleaning wipe, cotton swab, or microfiber cloth.
If the cutting tip is dull or damaged, and cannot cleanly cut through the
coating, it should be replaced with a new cutting tip.
If the built-in light does not power on, ensure that a new battery is
installed in the correct orientation.
Limited Warranty, Sole Remedy and Limited Liability
DeFelsko’s sole warranty, remedy, and liability are the express limited
warranty, remedy, and limited liability that are set forth on its website:
www.defelsko.com/terms
www.defelsko.com
© 2024 DeFelsko Corporation USA All Rights Reserved
This manual is copyrighted with all rights reserved and may not be reproduced
or transmitted, in whole or part, by any means, without written permission
from DeFelsko Corporation.
DeFelsko, PosiSoft, PosiTest, and PosiTector are trademarks of DeFelsko
Corporation registered in the U.S. and in other countries. Other brand or
product names are trademarks or registered trademarks of their respective
holders.
Every effort has been made to ensure that the information in this manual is
accurate. DeFelsko is not responsible for printing or clerical errors.