In the last few weeks I have spent some not-inconsiderable time trying to buy connectors for, and then connect, my various gas sources to my vacuum system. It's been a minor UNF/UNEF/NPT/NPTF/BSPP/BSPT-adapter-nipple-plug'n'cap-reducer nightmare!
After finding out one of my two regulators leaked across the valve, and the other [which I knew] is a bit low and can't use it for all gases, fortunately the god of ebay offered me a multi-stage 300-down-to-10 bar regulator, specifically for flammable gases. Perfect... now some more thread sizes to find... (who the h*ll uses 1/2" UNEF!?!?).
Anyhows, in fiddling towards the optimum configuration, removal and refitting of components is the norm. But I have yet to develop a good and effective method of cleaning off used teflon tape off of threads. It's pick-pick-pick-pick, whilst all the little bits static-cling to your fingers and you can't brush them off! ....
Any tips?.....