Yea, and flight hardware just adds PITA factor. Your in for a treat, I like doing 4130 (it actually cuts pretty easy when its around Rc35) compared to some of the crap I have had the "privilege" of working with. Inconel, Invar 36, Hastelloy, those are "fun".I haven't had the misfortune of either such terror, 30yr old German code or Ball-smashing, but i'm pretty new to the field.
Plenty of other stuff I've had to do is pretty terrifying though. Right now its Boeing wanting a bunch 4130/40 parts... uugghhh. Took 2 weeks to finish Roughing, and now I wait for them to return from heat-treating...