Something I started to notice recently, and I'm wondering what is causing it:
I use the Hollis DC-1 first stage for everything (backgas, sidemount, stage, deco). I notice that in between services it becomes progressively easier to "rotate" the first stage regulator radially after its been screwed in to the tank valve/manifold.
I took the regulator apart and didn't see anything obvious. When the regs were new/recently service, once you pressurized them...the first stages "stayed put". Now, they very easily rotate.
Useful thoughts, please.