Hello, We are working on over molding part in which Brass over mold with Nylon 6 30% GF. Design like cylindrical brass part with knurling or some grooves from over molding face and plastic covered with open one end like cap design. After over molding we find some samples having air leakage from joint between plastic after testing 120 psi pressure. Also some samples are tested with maximum 80° C temperature and after testing with 120 psi pressure find air leakage from joint between plastic. How will be avoid air leakage. We take lots of trail please advice solution.