What is a good adhesive to use when gluing metal to rubber?

A good adhesive to use when gluing metal to rubber is 3M Neoprene High Performance Rubber and Gasket Adhesive 1300. It bonds most types of rubber to most types of metal and usually dries within 12 minutes.

3M Neoprene High Performance Rubber and Gasket Adhesive 1300 is a high-strength, synthetic rubber-based adhesive. It is heat-resistant for rubber and metal.

To apply this 3M adhesive, either squeeze or brush it onto the part of the rubber that is to be adhered to the metal and then join the rubber to the metal. Always use this adhesive in a well-ventilated area, as it is toxic and highly flammable.