when i use contact cement on a tape patch should i let it dry first

Question

I used bultly tape to fix a leak i know i have to sand it first then was told to use contact cement before i put on liquid roof my question is should i let the contact cement dry then apply L Roof

Answer 1

that is correct the contact cement does need to be dry

Thank you

Answer 2

not the butyl tape only eternabond tape.  the butyl tape is a two sided sticky tape no need to do anything with is

 

Thank you