PREPARATION STAGES OF METAL SURFACES BEFORE APPLICATION
The metal surface must be completely cleaned before applying the adhesive. A good preparation of the metal surface is required to obtain a good metal/rubber bond and to be resistant to water and corrosion. The oxide layers on the metal surface should be mechanically cleaned. The metal surface is basically prepared by two methods.
Mechanical Cleaning:
Grit blasting is a recommended method of metal cleaning. Steel grit is used to blast clean steel, cast iron; for other nonferrous metals, the use of aluminum oxide is recommended.
Layover time between blasting and adhesive application should be kept to a minimum in order to avoid oxidation.
Chemical Cleaning:
The process of preparing the metal surface chemically requires a different application for each metal group. Phosphating is a widely used chemical process for steel. The process applied under the paint in the aluminum surface coating process is called chromate.
APPLICATION
Mixing – KA&MELOCK MP 42 should be stirred thoroughly before use and during using to keep dispersed solids uniformly suspended.
Applying – Brush, roller, dipping or spraying methods can be applied for KA&MELOCK MP 42.
• Brushing/Roll Coating Apply full strength.
• Dipping Undiluted or 20 % dilution with MEK
• Spraying Dilute primer with up to 40-60% of MEK
Experience has shown the following thickness of Primer and Bonding Agent provide the best result:
Apply for the recommended dry film thickness of 3 – 15 μ on sandblasted surfaces and approximately 5 μ on phosphated surfaces.
Drying- The bond coating can be dried at least 30 minutes at room temperatures. By using hot air drying up to 70 °C.; the time can be shortened. When dry, KA&MELOCK MP 42 forms a grey film on the metal part, providing excellent corrosion protection.
Metal parts properly primed with KA&MELOCK MP 42 can be stored for several weeks in a clean environment.
Clean Up- Use MEK for clean-up.