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Soft copper or PEX what's your opinion?

SuperRA

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I just built a new ceiling/attic floor in my garage to store stuff above. I want to run a single compressed air line from my small compressor in the corner of the garage inside the ceiling to a hose reel I'll hang in the center. I've pretty much hidden everything in the walls, so I don't really want to have it exposed, and since it's one continuous run, I have very little worries of leaks since there are no connections in between. I don't think it's possible to feed hard copper up into the joists which is why I am thinking of something bendable like PEX or soft copper. Besides, IF it does ever leak, then I could just abandon it and run another line externally.

What do you guys think?
 
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ADSR

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Im going with pex myself. Easy to work with and cheap to buy. Its tough as nails too.
 

Ron Fletcher

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Inside a structure, I would use copper. If I were running a water line to a garage that is an outbuilding, I might use PEX underground. Inside a building, I know copper will be there long after I am gone. But that is just me. PEX will do just fine. I'm just finicky. :dunno:
 

icsamerica

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pex

I'd choose Pex over soft copper based on price and flexibility. Why not used normal hard copper lines. Notch the joists or use a hole saw. They will out last the house. Sweating connections can be tedious but when you consider the longevity and durability of hard copper its hard to beat. Soft copper and pex cant make sharp bends so you will likely have loops in your attic which can be in the way and may get damaged when moving stuff around.
 

icenfire01

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It might just be me, but I hate copper. I can't get the sweat fitting thing figured out. I'm slowly replacing all the copper in my house with pex. So much easier to run and work on. I understand that copper is much more durable but honestly how often are you working on ANY plumbing lines?
 

383 240z

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Wife has me gutting the laundry room next. I think I'm going to use PEX, main reason is I want to play with it. Never used it before this is a nice small project to try it out on. Main reason I considered it was the dryer. I need to run a water line to it, so that make 3 cold water supply lines on the same wall. washer, dryer, and sink.

I saw a manifold at the plumbing supply house that will work great. If I can find a way to build a 3 hose bib manifold from copper, I might go that way. Save me from buying a few tools, I'll only use once. Keith
 

CNGsaves

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^ ^ ^ 383 . . . you need to just Delete above post. OP is talking about soft copper or "pex" for AIR LINE system up in attic of his garage. He is not talking about water.

OP, both of your ideas for AIRLINE SYSTEM up in hot attic (ie either soft copper or "pex") are inappropriate. Use neither one. First time you have to get up in attic, you will tear up that makeshift air line system made of inferior material.

DO It Right, and install hard copper or black pipe steel. Put slope on the line so any moisture flows to where you have a drain. While you are planning out a good air line system, run hard copper or black pipe steel over near your bench so you will have drop handy there. See excellent thread on airline system by Strouty. Good luck.
http://www.garagejournal.com/forum/showthread.php?t=214394&highlight=air+line
 
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ADSR

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Copper is my choice. If you do use PEX it must be for air.



i'm going to call BS on this. When i asked my plumber about it, he pressured a regular piece of pex 20' long up to 250 PSI. Nothing happened. It will be fine for my system of 125 to 175 PSI.

Hell, the last 15 years i've run thin PVC and never had a problem at 125psi.
 

big.jim

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normal pex isnt rated for oil contamination from your compressor that is why there is an air rated pex this is just to cover their ****
 

C96

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Forget about the Pex **** and the soft copper. Soft copper is exactly that, soft. Both the Pex and soft copper will have dips and sags in the horizontal runs providing areas for water to accumulate. Go with the hard copper or black pipe as CNGsaves suggests and run the proper slope and drip legs.

I personally prefer the black pipe run exposed. It’s easily serviceable, easy to add-on to, strong at the service points and does a great job cooling the air so the water drops out. The Pex will not be of much help with dissipating the heat.

Do it right / Do it once

Good Luck
 

ADSR

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Black Iron FTW!!!

PEX is for hackers...

I'm a hacker and proud of it. It's very cost effective and will last 60+ years no problem.

Black iron is great too. But it's more costly and harder to work with.

Hard copper is just too much money.

I'm cheap, lazy and want it done fast. Pex is for people like me.
 
OP
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SuperRA

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Thanks for the replies guys.

Let me clear some things up. The lines won't be exposed in the attic nor the garage. There is plywood on the top and there will be drywall on the bottom of the joists. Any hard plumbing solution will not likely be feasible as I can't see how I'd get it up in the runs perpendicular to the joists. That is unless I use several small pieces and join them together or notch the joists, neither of which I want to do. That's the reason I want something flexible so I can install it. And hey, if it doesn't work, I can just cut if off, close it up and run an ugly (IMO) external line!

Also FYI, I'm not afraid of soldering copper. I used to solder and braze copper all day building cooling equipment for data centers.

Thank you BD1 for the PEX links. I was wondering if the PEX had to be special for air vs. water.
 
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BD1

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i'm going to call BS on this. When i asked my plumber about it, he pressured a regular piece of pex 20' long up to 250 PSI. Nothing happened. It will be fine for my system of 125 to 175 PSI.

Hell, the last 15 years i've run thin PVC and never had a problem at 125psi.

If a product is RATED for air use, it will say so. Check with manufacture and see what they say about it . Just because YOU used it doesn't mean it is SAFE or LEGAL PER CODE. As far as PVC :scared::scared: You are LUCKY, go buy a lotto ticket. PVC is against osha and the MANUFACTURE EVEN STATES IT !
https://www.osha.gov/dts/hib/hib_data/hib19880520.html

READ THIS . http://www.garagejournal.com/forum/showthread.php?t=89186
 

LS6 Tommy

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To my knowledge only pex-al-pex is rated & certified by the manufacturers for compressed air. There is nothing wrong with using ductile (soft) copper if you don't mind the cost, but you need to use L, K or ACR. M is not rated for compressed air.

Tommy
 
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SuperRA

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Wow, copper is expensive! What do you guys think about bendable aluminum tubing! It's rated for the pressure and costs less than the pex for the amount I'll use.
 

sni-per

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I wouldn't be afraid of using the PEX for air. After all, they have been using plastic air lines on trucks and trailers for about 50 years now. PVC on the other hand, I've personally seen explode, being used for air. I have my compressor in my back shed, with PEX running through a buried conduit, to my garage, roughly 40 feet away, and only drop about 7 pounds of pressure to the manifold. I've had that setup for about 15 years now, and no problems.
 

CNGsaves

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Thanks for the replies guys.

Let me clear some things up. The lines won't be exposed in the attic nor the garage. There is plywood on the top and there will be drywall on the bottom of the joists. Any hard plumbing solution will not likely be feasible as I can't see how I'd get it up in the runs perpendicular to the joists. That is unless I use several small pieces and join them together or notch the joists, neither of which I want to do. That's the reason I want something flexible so I can install it. And hey, if it doesn't work, I can just cut if off, close it up and run an ugly (IMO) external line!

Also FYI, I'm not afraid of soldering copper. I used to solder and braze copper all day building cooling equipment for data centers.

Thank you BD1 for the PEX links. I was wondering if the PEX had to be special for air vs. water.

First, you have NOT done NEARLY ENOUGH research as you somehow have distorted idea that water pex will work for airline . . . No, NO, NO !!

Also, never, EVER, NEVER notch any ceiling or floor joists to do makeshift half-*** work that you are considering. There would be absolutely no problem with black pipe steel running across the TOP of ceiling joists or whatever plywood you have up there in attic. Just add appropriate hangers to hold up the weight of black pipe steel air line system.

Don't understand your concocted notion that you can't have surface mounted airline system on ceiling of garage, but yet you are dreaming up ways to notch ceiling joists . . . WTH ?? Pop hole through ceiling, then run the black pipe steel ABOVE the ceiling joists across attic.

Take out gable vent on edge of house and get your pipe into attic that way. You can get 21 ft sticks of black pipe steel from commercial plumbing supply house, or cut to length you need. This is NOT rocket science . . . . more like putting together tinker toys.

Do It RIGHT . . . and Do It Once !! :D
 
OP
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SuperRA

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First, you have NOT done NEARLY ENOUGH research as you somehow have distorted idea that water pex will work for airline . . . No, NO, NO !!

Also, never, EVER, NEVER notch any ceiling or floor joists to do makeshift half-*** work that you are considering. There would be absolutely no problem with black pipe steel running across the TOP of ceiling joists or whatever plywood you have up there in attic. Just add appropriate hangers to hold up the weight of black pipe steel air line system.

Don't understand your concocted notion that you can't have surface mounted airline system on ceiling of garage, but yet you are dreaming up ways to notch ceiling joists . . . WTH ?? Pop hole through ceiling, then run the black pipe steel ABOVE the ceiling joists across attic.

Take out gable vent on edge of house and get your pipe into attic that way. You can get 21 ft sticks of black pipe steel from commercial plumbing supply house, or cut to length you need. This is NOT rocket science . . . . more like putting together tinker toys.

Do It RIGHT . . . and Do It Once !! :D

Nope, never said that it would be ok to use water pex. That's why I thanked BD1 for the links to the real air pex. Also if you read just past the portion you highlighted in my quote I said that notching wasn't something I wanted to do. Also I never said I can't have a surface mounted pipe,just that I DONT WANT a surface mounted pipe. For the purpose I built the ceiling for, I don't want anything running on the top surface. It is more important that it stay smooth than for me to even have this air line. Both the top and bottom of the joists will be finished surfaces so the pipe will have to run through bored holes in the joists just like Romex wire.

Again, I mean no disrespect to you or anything. I happen to agree that hard pipe solutions are superior. but a hard pipe solution just isnt an option for this particular project. That's why I asked only about flexible pipes like copper pex and aluminum.
 
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oldtractors

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PEX. My system has been up for 5 years now with no issues. I have the ability and tools to do black pipe, but I only use black pipe for steam.
 

wdrumheller

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I've been using PEX for 5 years for my air line systems and it's been great so far. Not a single leak, easy to install, and it just does the job.

I'm pleased with PEX. I'm running 80-120PSI at all times on my pex, and I like it.

I may be proven wrong with time, and to be COMPLETELY honest I did replace some pex when I moved my compressor to my new shop, and the old pex had become somewhat brittle right near the compressor, so maybe I'm a fool. A happy fool, but a fool nonetheless.
 

Clik

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How does the plastic used for airlines on big trucks compare in price with residential Pex?

Obviously big rig air brake lines would have to resist oil, heat, cold, vibration, etc.
 

Mr onetwo

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Guys...the air lines used for heavy transport brake systems IS NOT PEX! The material used is a type of nylon used and rated for air service.You could use this in a compressor system, but I believe it is quite expensive in larger sizes as are the fittings.
 

gc427

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I love threads that ask for opinions. :scared:

My opinion is neither one. PEX is not rated for air and soft copper is too easy to kink but it will work ok.

My vote is for black iron pipe.

For all of the PEX lovers out there I have to ask how do you know that it will hold up long term? This stuff is fairly new and has a short track record. It looks promising but only time will tell.
 

amac70

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I love threads that ask for opinions. :scared:

My opinion is neither one. PEX is not rated for air and soft copper is too easy to kink but it will work ok.

My vote is for black iron pipe.

For all of the PEX lovers out there I have to ask how do you know that it will hold up long term? This stuff is fairly new and has a short track record. It looks promising but only time will tell.

pex has been around and in use for more then 40 years, How long does it need to be around for your long term testing? I don't have a problem saying use it but know its limitations, it is also not uv stable so keep that in mind. If you can swing it step up to the pex al pex.
 

tshetter

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Yea, why not just use air hose? Get a few 50/100 ft Goodyear black or red air hose and run it.

And if you really need it run through the center of the joists the hole will be one inch.

All this PEX and copper talk is over thinking it. Black iron is good and all but you need to thread it get all your elbow and union fittings.


If you want to run air lines run some airline. Hard pipe a few feet off of the compressor with a valve to drain moisture and be done.
 

Capt Chrysler

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Funny this would come up.last week at work we had the the plant go down do to a burst plastic air supply line (No this was not a PVC line.) She popped just after on of the fittings after the AquaCheck filter. When the production manager showed me the hose it showed signs of harding about 2 foot in length. But the funny thing is, none of the other lines showed any signs of failure. So I think maybe the filter may have been added some heat to the air and this caused the problem. Not sure. The rest of the plant and shop at home are hard lined. If ya got the $$ go hard line. Even black pipe will work.


Capt. Chrysler
 
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