I have a 1-1/2" cast iron show drain. will attach to 1-1/2" abs male threaded coupling. Do I need to put pipe thread or plummers puty on the threads?

Plumbers putty is no good for threaded joints. When you have plastic(abs,pvc) threaded joints, you need to use teflon tape on the threaded portion. Do not use liquid pipe dope, or sealant. Teflon tape only(on plastic threads).

OK great... so put on teflon tape on the male abs threads which will thread into cast iron... thanks.

Yep you do that and you should be all set. Make sure that the cast iron female threads are clean and you'll be just fine