Drying Time Tester Model 415

The Model 415 dryness tester is used to determine the degree of dryness of coatings according to ISO 9117 (the modified Bandow-Wolff method). It consists of a light metal cylinder which is attached to a stand. The compression spring built into the cylinder can generate a stamping load of up to 250 N. A lever mechanism is used to apply this force perpendicularly to the coating. The distance between the stamp and the stand's plate can be adjusted by adjusting the lever to match the sample thickness. For a standard load under 2 kg (20 N), the load weights (of 20 g and 200 g) with a diameter of 24 mm are included with this product. To achieve a uniform distribution of the contact pressure a cylindrical soft rubber disk with a diameter of 22 mm, a thickness of (5 ± 0.5) mm and a hardness of (50 ± 5) IRHD in accordance with DIN ISO 48, is used.

Performing the analyses

The test sequences vary in accordance with the dryness degree as follows:

• Dryness degree 1
  • The coating is covered with ballotini which are subsequently removed using a fine brush.
• Dryness degrees 2 and 3
  • First a paper disk is placed onto the coating, then a soft rubber disk. Loads of 20 g and 200 g are applied by adding one of the individual weights provided (load duration 60 s).
• Dryness degrees 4 to 7
  • The test panel is placed on the stand base with the coating upward and successively covered with a paper disk and a soft rubber disk. The required load (2 kg or 20 kg) corresponding to a plunger force of 20 N or 200 N, is produced using lever pressure and maintained for approx. 60 s.

Evaluation of Test

After removing the load, the coating is evaluated in accordance with the following table.