It may be it was always there and I missed it OR it accumulated later. Either way, I don't know what it is. Mostly crusty, a little sticky, and a damp rag can eventually cut through it.
I've already removed some on one side with my leatherman but will hit it again with a proper blade when I get a moment.
I've already removed some on one side with my leatherman but will hit it again with a proper blade when I get a moment.