Air filter/reg question

[_Ogre]

depends on the flow requirements.
if your a one man operation with one air tool being used then 1/2'' is good/cheaper
check the cfm rating of any main line regulator, some of those cheap ones can be low flow

i run a 1/2'' filter/regulator in my barn, but i also ran 1/2'' copper for my lines
in our commercial shop i have a 3/4'' 50 cfm filter/regulator on 1'' lines
my barn is one man, the shop typically has 5 guys working, cnc plasma table and a paint booth