what size pvc should i use? i'm thinking 1/2" to keep good pressure . ingersol rand 2 stage with a 80 gallon tank. max of 160 psi. wanna run 3 legs , or should i say 1 in each corner. any thoughts or suggestions ?? shop is 30 x 40.

PVC air lines are no goog. Go with copper, more work but worth it. All of the compressor manufacturers specify not to use PVC. I have had one shatter and got a piece in my arm, that was no fun. Size depends on what ou want to run with it, for my 1" impact gun I need atleast 3/4" to keep up, jitterbugs use a hell of a lot of air too. you would probably be fine with 1/2" but I wouldn't go any smaller then that. And I know everyone uses PVC but after the incident that I had I will never use it again.

I recently moved my compressor downstairs from the garage. Used all 1/2" black pipe. Home depot has all various lengths & configurations. Was a bit of a challange to do what I did but it all worked out.

Under no circumstances should you use PVC for compressed air.
Use standard threaded black pipe and fittings. 3/4 or 1/2 inch is fine. Make sure you put a water drain at each drop. Use a short flexible line from the tank to your hard pipe.

I have seen shops that had PVC air lines.I have had plenty of glue joint failures here at the plant.I have My shop at home (5hp) is set up with a High Pressure 1" flex line from compressor to wall then 3/4" black iron pipe to a Filter then up to about 7' off the floor. At each drop use a 3/4" x 1/2" branch T turn the T up so the air comes out the top of the pipe and use( 2) 1/2" street Ls to make the turn down.Install a 1/2" T at the level that U want the air fitting to be and run a 4" drip leg with a drain valve on the bottom.Also run your 3/4" header slightly downhill so that water will run to the last leg .

my problem is down here in the swamps we get alot of humidity and that steel pipe sweats , so does copper. at work we have a serious air drier for painting . i'm not planning on doing a ton of paint work here but would like dry air. i know pvc won't sweat. i have some sharpe 606 filters to put at each outlet. i was planning on doing a double "U" type of pluming right off the main feed from the unit with petcocks at the bottoms to drain out water. sound like a good idea?

We have the humidity problem too (Florida) We used copper lines and took care to make all horizontal lines drop towards water traps (we didn't use "U"s just a pipe hanging down a couple of feet with a faucet under it.) we also have water separators at every outlet -- to no avail. You can use chemical driers buy here they last all of three minutes...
We talked to the compressor people and the only solution is an air drier. What it does is to cool the air down to get rid of the water and then, get this, heat it up so that your pipes don't sweat!
Fortunately we're switching to a rotary compressor that has all this pre-built in it!

What pipe you use has absolutely no bearing on the moisture content of the air inside. Pull wet air in and you'll get wet air out- unless you remove it somehow.

PVC is dangerous. Explosions are very common. It's one thing to do something you know is dangerous and accept the risks but I'd guess other people will be around your shop. You go and blind one of your kids and you're not going to feel so good.

Iron has a tendency to collect "compressor goo" on the inside as it has a rough surface- It's actually a bacteria that grows in there. Over time, you'll get restrictions, especially in elbows. Copper is what you're going to find in virtually all new commercial/industrial installations today. Remember to use a bronze fitting between the copper and the steel tank or you'll have electrolytic problems. If you don't sweat copper very often, keep these things in mind- clean both the male and female ends with a brush or emery and don't over-heat. Move in and off with the torch until the solder flows easily. Too hot and it will flow right out and you'll be re-soldering leaky joints. Remember to use unions and don't solder too close to a freshly doped or taped threaded connection. There's nothing more frustration than hard plumbing a whole system without unions to then find out you melted the teflon tape out of the compressor tank bung

We install basic separators on systems in very humid places in NC, SC and TN and have no problems with air tools. Traps are going to fill up in a few minutes without separators so how many and how large really doesn't matter. We have service contracts with some of our customers and some of them think that relieves them of the need to drain their tanks regularly. I've seen 8 to 10 gallons of water come out of an 80 gallon tank after a month of un-drained use. An automatic drain is cheap and easy to install.

If you want to paint and don't want the effects of water, a dryer is about your only choice. If you're in a high-humidity area and you need dry air for painting on more than an occasional basis, you'll spend more on dessicant filters than the cost of a dryer. Dryers- at least decent, American-made ones can be pricey. On a 5HP/3PH commercial-duty compressor, it adds almost 70% to the cost. You can get a decent Quincy 25CFM unit for under a grand. If you don't use it 8hr/2 shifts, it will last a good long time.

It astonishes me how many "professionals' fight putting a dryer in their paint shops. I've talked to body guys who have spent thousands on seps and dessicants and THOUSANDS in lost time re-shooting fouled paint over years and years. They buy a dryer and suddenly their overall paint quality comes up and their work time drops- not to mention the wasted materials. In a production shop, a dryer pays for itself in 90 days. Then I get to hear "why didn't you tell me before?" Uggghhh.

chris , thanks for that information. i will snap a pic of how i want to run it and then tell me what size copper to use.

i don't know how to figure distance x width on the pipe size.

ah ,the power of OSO !!!

thanks !!

If this is a home or small commercial shop, you'll want to run 3/4" everywhere. That's going to accommodate a 5HP or even a 7.5 with two users. It will run a 1" impact with no loss. If for some reason you need to, you can reduce your drops to 1/2. If you do, use a 3/4 tee or elbow, then reduce to 1/2". Most line losses occur in the hose and QD fittings anyway. You usually won't notice until you have an air-hog like a 3/4" or larger impact in use. Try to always use ball valves. Anything else is going to give you losses. For ease of run, we usually like to go up high with a main run- that way it clears doorways. Make sure you have at least 1/4" per foot of run in slope going out. You need to tee down at the compressor outlet and at any drop. Give yourself 6" to 8" and a pipe plug on the end will do the trick. Put ball valves at each outlet connection. If you don't mind spending a few more $$, put ball valves there as well for your drains. If you're in high humidity, it makes servicing them easier which makes it more likely you'll do it. Another trick I like to use is to put two outlet fittings at each termination. That way, I can plug in the small hose or the big hose, whichever I need at the time.

This is a very good place to buy just about any of the hard-to-find pieces you'll need. They are about an hour from me and I occasionally find they're cheaper and better stocked than some of the manufacturers we deal with. http://www.tptools.com


Feel free to send a pic or ask whatever questions- always happy to help.