DUBAN DB20-LX-P Pencil Hardness Tester paints Hardness Gauge

DB20-LX-P

Pencil Hardness Tester (paints Hardness Gauge)

100G/750g/500g can replace three kinds of loads, in line with the standard Coating pencil hardness testing indicators, with 1 set of 6B-6H pencils, eraser X1, pencil sharpener X1, horizontal pad X1, No.400 sandpaper X1.

The hardness of the coating film is a necessary index for the identification of coating performance. The Pencil Hardness Tester uses the pencil scratch method to quickly and cost-effectively determine the film hardness of an organic coating on a substrate using a drawing lead or pencil lead of known hardness. The pencil scratch method to test the hardness of the coating film is a test method that has been widely used internationally since the eighties. CHINA has also promoted this test method in the development research and industrial production of coatings. The instrument can be used in the laboratory or on the construction site.

Test principle

     The instrument is mechanical, and the three-point contact with the measured surface (two points are wheels, one point is the lead core) always ensure that the pencil is at an angle of 45 ° with the test surface, and the instrument is pushed to slide by hand, and the pencil draws the corresponding trajectory on the paint film. Different pencils are used to draw different marks, and the hardness value of the coating film can be determined.

Test board provisions

1. Measurement procedure

Unless otherwise requested by the customer or otherwise agreed, the test sample will be taken from the product after the coating process has been completed; When the width or length of the coating surface of the product is less than 1cm, a test sample needs to be made, and the sample size is 50x120 mm or 70x150 mm flat plate, and the coating application process needs to be consistent with the product process.

2. Regulations for test pencils

Use a sharpener to cut off the wooden rod part, so that the refill is cylindrical and exposed about 5~6mm, and do not loosen or cut the refill. Then place No.400 sandpaper on a hard surface, draw circles with the refill vertically against the sandpaper, and grind until the nib is ground into a flat surface with sharp edges, and the edges must not be broken or chipped. (The pencil should be rotated 180° after one use or re-sharpened)

3. Test steps

3.1 Take out the horizontal cushion block, observe the level indicator mark, ensure that the bubble is between the two marking lines, if the bubble is not between the two marking lines, then re-adjust the bubble so that the bubble is between the two marking lines, and then measure. Advancing at a speed of 1 mm/s, the pencil draws a line on the surface to be measured. Loosen the set screws, rotate the pencil 180° or re-grind, and draw another line.

3.2 Place the horizontal pad under the instrument body. Take out the pencil prepared for the corresponding specification (starting with the hardest lead) and insert it diagonally into the hole on the inspection trolley at an angle of 45 degrees. The pencil refill extends just enough to contact the surface of the sample to be measured, tighten the fixing screws so that the pencil cannot be loosened. (According to the test product test requirements, choose whether to increase the weight).

Draw the line at the same position 5 times, it is recommended that the length of the pen line is 6.5mm, and check the appearance and function after wiping the measured product with an eraser after the marking is completed.

Pencil selection during the test: according to 6H-5H-4H-3H-2H-H-HB-B-2B-3B-4B-5B-6B

3.3 Scratching of the coating film: If two of the five times can plow the coating, then use a softer pencil until at least four of the five times can not plow the pencil of the coating, and the hardness of the pencil is the hardness of the pencil of the tested coating.

4. Precautions

• When sharpening a pencil, it is important to note that the shape of the sharpened refill must be cylindrical.

• When loading the pencil, it must be padded with a balance pad on the lower part of the front end of the trolley, so as to avoid the angle difference of the loaded pencil.

• In the process of pushing the trolley, do not use too much force to be able to push the trolley in front of the trolley, so as not to break the refill.

• Each time you push forward to test, you must loosen the fixing screw, twist the pencil, change the angle of the pencil, and then fix the test. 3H-2H-H-HB-B-2B-3B-4B-5B-6B hardness decreasing measurement sequence, if the approximate hardness of the test sample can be clarified, then raise the two standards to start the test, gradually replace the softer pencil, and obtain the final test data.

• It is recommended to wear gloves to use this instrument to avoid rusting of the instrument.

• Before using the instrument, test the appearance and function to ensure that the test sample functions normally, and the appearance is free of damage, cracks, scratches, etc., and the surface is smooth and flat.

Packing list：Pencil hardness tester X1, 1000g weight X1, 750g weight X1, pencil (6B-6H) X1, eraser X1, pencil sharpener X1, horizontal pad X1, No.400 sandpaper X1

[Note]Because the manufacturer's packaging may be updated or upgraded, the detailed packaging list shall be subject to the latest standard configuration of the manufacturer.