I need to get putty off pipes in between 2 pipes

Separate the pipes and use a wire brush

As stated or an ice pick or triangular file.

You don't put Plumber's Putty on pipe threads. We use Pipe Dope ( many different types with various consistencies and setting time ) or teflon tape. Some of the Pipe Dopes remain flexible while some harden shortly after installation. I agree with the above advice: use a steel wire brush to clean old Pipe Dope. Hope that helps. Let us know how you did. Back to you. Milo