Glue Rubber to Metal

Rubber to metal bonding provides an air and water tight seal between these two differing materials. This is accomplished by gluing them together with a bonding adhesive, also called a primer, cover cement or tie coat. Originally, bonding adhesives were solvent based. However, in recent years a switch has taken place; water based adhesives are now more popular because they are much better for the environment.

Key to the rubber to metal bonding process is choosing the appropriate adhesive. It insures the product is able to withstand the environment it will be required to operate within, whose variables may be vastly different. The bonded rubber and metal product may be in an environment where the temperature is high, where high pressure is frequent, where there is constant vibration or exposure to moisture, chemicals or oil.

Without the bonding glue, these products would fall apart easily and not form a lasting seal between each other. Rubber bonded to metal products are used often in the automotive manufacturing, aircraft, industrial machinery, storage, electronics, engineering, construction and plumbing industries, among others and are fabricated into many useful parts and products for industrial uses.

These products include vibration absorbers, which work as buffers in environments where vibration causes problems; rubber lined pipes/tanks, bearings and electrical cords. The glue itself is long lasting, flexible and cures as the rubber dries in the mold around the metal substrate, which can take a varied amount of time depending on what adhesive is used.

When metal and rubber are glued together with a bonding adhesive, it is usually applied by a low pressure, high volume spray gun that evenly coats the entire surface of a metal substrate. This is done after the substrate has been fabricated and thoroughly cleaned with a sand blaster, degreasing agent and sometimes chemicals.

It is applied in two coats; first a primer then a black colored top coat, prior to the molding process. The type of adhesive used depends on the type of rubber and metal being used, as well as the environment the future part will be subjected to. It must also be specifically matched to the type of vulcanizing or molding process.

If the part will not be subjected to high humidity or fuel and oil, a one-component adhesive system can be employed if desired. However, the primer adhesive is very important and directly affects the bond strength and the performance of the part under pressure. The most popular glues for metal and rubber bonding are water based and made from high molecular weight emulsion, pigments and curatives all mixed together in water, and are considered as effective as solvent-based adhesive systems.

Glue Rubber to Metal Informational Video