Worked straight off for me. I did PAM's mission, got stuff from somewhere, Then did Tinkers mission put thing on top of building. Talked to Tinker a few times. He now stocks armoured clothing and I can weave at Armour Workbench.
What does wont let me mean?
When your at a armour workbeanch can you select outfits that were not selectable before? Are the weave options there but grayed out?
My guess is that you did not talk to Tinker Tom enough or at the right time. I am still confused as to whether its PAM or Tinkers's missions that trigger it. I complted one of each than had to trigger a converstaion with Tinker twice to get the weave.