hey guys im just wondering what size you use for your air lines. my compressor is 240volts 7hp 80 gallon tank around 16cfm and max 175 psi... and i wont be using pvc.......
It's going to depend on your use, if you are just inflating tires 1/2" is overkill. Probably better to have some sort of splitter where you can plug 1/4", 3/8", and 1/2" into it. There are uses for all 3. ehh?
1/4" is too small for anything other then an air brush. 3/8" I.D is the general size most people use. It's big enough to run most tools, yet thin enough to carry around easy.
1/2" air hoses work best for high CFM tools such as orbital sanders, impact wrenches, HVLP spray guns etc.
With the specs of your compressor I would recommend a full 3/4" I.D hard line (black iron pipe) with a filter/lubricator combo and then get a good 50' 3/8" Goodyear air hose to use for general tools and maybe get a 15 to 25' 1/2" air hose for large tools if you have any.
I have a compressor with similar specs (about 200 psi, 7.5 hp, 120 gallon) and I use 3/4" piping. 3/8's ID hose (I htink 23/32 OD) and 1/4 fittings. Some fittings are 3/8's (the 2 Cox hose reels I have). This set up takes care of anything I need. Impact, air for cleaning, painting, running angle grinders, blast cabinet, etc.