copper vs. black iron for air

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Central (upstate) NY
I had one of those rare epiphanies recently. If I moved the medium sized upright air compressor to the basement I could free up a tiny bit more space in the shop.

I'd need to run some piping for it though. If I went copper I'd use the expensive Oatey silver bearing solder because I cannot get a good sweat with the cheaper lead stuff (tried before to run some air in the basement for the little compressor - failed miserably, but I did successfully install a utility sink with no leaks :dunno: :huh: ). I have a little copper on hand leftover from the failed attempt of basement air and the utility sink (I bought big contractor packs of fittings so I wouldn't need just one more to finish the task).

Iron might be a little easier to work with, but I'd need to buy everything fresh. Maybe if I bought extra I'd have an excuse to buy pipe clamps (quote of the day from my wife, "What is the deal with all these clamps lately?").

I suppose another option is just to get a couple 50' or 100' lines from Harbor Freight and be done with it.

I mostly use the compressor with the impact wrench for vehicle maintenance. Might get a pneumatic drill if I get into turning more and pick up one of those sanding pad sets.

What are the pros and cons of each possibility? And did I forget anything? On the off chance it matters, I'm using ARO style connectors.
 
For my air lines I went with galvanized pipe. Black iron also works well (ask Tod), but I splurged a few extra bucks to go with galvanized, mostly for the look more than the protection. Copper is considered my some folks to be the best, but it's considerably pricier. (This may be moot point it you already have most of what you need.) Iron pipe is more resistant to impact, so if you bang it with something accidentally you're not likely to mess anything up. My bar clamp rack was installed over my air drying rack, so I wanted something that could put up with getting banged by Besseys on occasion.

Here's how it looked before I filled the empty floor space with the compressor:

Air System 32 - 800.jpg

Personally, I'd recommend against using a couple hoses for your supply lines. I'd think it would be harder to control (gather) the condensation, plus I'd be leery of the long-term durability. You really don't want to be around a broken hose at 135 PSI. DAMHIKT.
 
I ask my plumber this question he is also a builder & electrician. He said regular copper like you would plumb a house with for a small shop that run normal pressures you would expect to find in a small shop is fine. Its what he used in his shop. I have it in my shop with no problems & I used the regular solder too.
 
Compressor in basement? Mine goes into another room accesible from an outside entrance with the new shop am building this summer. I saw the aftermath of one of those little ones on wheels that blew sitting on the concrete apron of a guys home and a large one that blew at a body shop in Randolph Co.. It isn't pretty and wouldn't want to be sitting ontop of one of those. I might be all wrong and remembering two different things and putting them together as one, but if you are installing air lines in your concrete floor, you don't want to use copper because it reacts/breaksdown over time with exposure to concrete? Good luck on what you do and how you decide to do it.
 
The lines will be hanging on walls / ceilings.

Vaughn, thanks for reminding me about moisture traps - don't think of it right now (sporadic non-spray use / dump pressure when done each time) but if I do get into spraying I'll want moisture free air.

I know I'll want a port near the overhead door to the garage to bring the line outside for car repair. Maybe another port by the assembly table / lathe station and maybe one more towards the rear of the shop for spot blowing? Although I could just run a longer hose for spot blowing. For that matter, I'm able to reach the cars from the compressor currently located at the rear of the shop, so maybe just a single port near the assembly table? Need to make sure it doesn't interfere with the overhead door if I do just one port. For that matter, no port should interfere with overhead - don't want to invest in a fancy HVLP gun and leave it plugged into air, sitting on workbench and then wife open overhead to bring in groceries and BAM!

Anything wrong with using up the copper I have and supplementing with iron? Maybe run a short length of hose between the two? I'd probably use a short length of hose between the compressor and the pipe system anyway to eliminate most of the vibration - I know this is bad for solder joints, and can't be good for threaded joints.

Thanks for the replies. It might be awhile before I get around to doing this, but as I sit here wanting to do shop stuff but am limited by a slow healing back injury I'm thinking of ways to make the shop better, even if implementation will be awhile.
 
Within the 1755 post thread that detailed Marty Walsh's incredible workshop, he goes into detail about installation of black iron pipe (this part starts here) for his air lines.

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I have to warn you reading this post will take the better part of a day, but you will not be able to "put it down". He has a workshop others can only dream about.

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well frank ,thanks for the dream revisited:thumb: and that shot of the shop is old. its alot fuller now:D.. i too ran black pipe for the dryer system, and use good pipe dope or you will be chasin leaks forever.and it was from tods recommendation and me seeun how he did it..i got my filters from tp sales a good company and quick delivery..they have a diagram of how a proper setup should be from the compressor to the tool. also you are gonna want a rubber hose made for high presure, think hydralic hose to elimante the vibes between the pressor and the hard pipe
 
Pipe dope. I feel like a pipe dope now. :rofl: So a couple layers of teflon tape per thread joint ain't gonna cut it?

Any recommendations for pipe dopes (like me :rofl: )?

Another question - can the moisture trap piping be done right after the compressor and then run straight out to ports? My basement is heated and the shop is not, so if I'm leaving the system under pressure I should have at least a minor moisture trap in the unheated garage also, right?
 
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Both are good, both have their pluses and their minuses.

I like copper for a few reasons, one, it is dead easy to install, a torch, and a pipe cutter and you are on your way, iron pipe can be a bear to get everything to fit together, you have to think about how it all screws into itself, and even then, you usually need a few of the twist together joints.

The other nice thing about copper is that you can very easily tap into it where ever you want. Down the road, if you decide you really need to run a branch over there, just get out the pipe cutter, cut the pipe, and solder in a T and you are on your way :dunno:

As you have the copper now, I think you question may well actually be "Is there any reason I should NOT use copper?"

I'd say "no" use copper, it works good.

Cheers!
 
reasons to avoid copper;
1) doesn`t handle impact well.
2) doesn`t condense moisture as well.
3) requires dielectric fittings to transition to many fittings unless you pop for bronse or brass.
4) changes in layout require a torch in a woodshop.

as for pipe dope rectorseal for gas lines is available at the borgs......good stuff!
 
I plumbed my shop with ¾ copper about 10 years ago, and have never had a problem.

As for moisture traps, every place I have an outlet I use this setup, (see attached picture) Just burp the ball valve at the bottom to remove any water, the filter is probably overkill, but I wear a Belt and Suspenders just to be safe!

I used reuglar lead free plumbing solder.

Dan
 
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Wouldn't black iron after a few years = rust?:huh:

I know I don't like black pipe for pipe clamps.

If I had to use pipe I think I'd use galvanized. Suggestions on this.:thumb:

I still prefer copper.:D

I don't think I'll have a problem as far as going around banging into it. In my small shop I've had no such problem so far & the pipe would be much higher up in a garage er shop than its current 7'10" & if I could I'd run it over the top of the bottom of the trusses inside the ceiling & just have my drops showing.

In any shop I'd have my thoughts are to start a drop between bench & assembly table. A drop half way in the length of the shop on both sides & one by each of 2 doors. :D

Other recommendations welcome.:dunno:
 
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As you have the copper now, I think you question may well actually be "Is there any reason I should NOT use copper?"

I'd say "no" use copper, it works good.

Cheers!

I think Stu got to the heart of the question. I have seen copper used in many industrial applications, but I have also seen steel pipe and stainless steel pipe. There are many factors as to which material is used in each case, but they are not really relevant to your situation. If you already have copper, use it and it will serve you well.
 
Black pipe is what is the flavor of choice around here.

I still ask this question what about moisture & rust? You can have low point drains & moisture traps but there will still be some moisture in the line somewhere & thus a chance of rust. It not only weakens the system but if you don't have a filter on each drop you run the chance of small particles of rust getting into your nail guns or what ever you have hooked up to the system. Knowing this why would I put so much labor into this type of system when I can use copper with no rust & a lot less labor?
 
Yes the black pipe will rust out just like the tank on the compressor.
How ever my system is around 10 years old and I have yet to see any signs of rust.:thumb:
To add to what Chuck posted, when I was figuring out how to do my system, I talked to a guy who'd been in the compressor and air system business for 30+ years. He's seen (and removed) all kinds of pipe from old systems. He said yes, black iron can rust, but he never in his career saw or heard of a black iron air system having enough rust to cause problems, and he never saw a system fail due to rusty pipes.

The guys on the hot rodding forums debate this subject endlessly (about like the left tilt/right tilt debates on the woodworking forums). Despite a lot of folks worrying about rust in black iron pipes, I've never seen anyone actually having problems with it in an air system.

Just don't use PVC. ;)
 
Infinite WIZDOM!

well we all have been tight before and in my shop build i ran low on funds when i got intot he air department and i had pvc left from the old shop with fittings.. so that was what i used for the drop lines from the seperators to the drops the rest was like tods setup.. well i read vaughns post and had reminded me of what my had mentioned a few days ago,, and so i asked vaughn what his reasoning was and this is what he said: When it fails, it shatters into sharp pieces...shrapnel. Metal pipe peels open or splits, but PVC explodes. Also, with age it becomes more brittle, increasing the change it'll blow up if it gets hit with something in the shop.

There are always guys who say "I've used PVC air lines for 30 years with no problems", but they're flirting with the Devil IMHO.


so from me to the rest, if your using it change it i am! when two smart fellars tell me i am wrong i had better listen,, thanks vaughn for gettin threw:thumb:
 
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