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Scishopguy
08-18-2001, 06:03 AM
Copper is my choice for any air line installation. Easy to work with, won't rupture and make you mess your pants, and will not shower your work with rust flakes like black iron. We had black iron at work for years and the compressor was in a small room across the hall with no ventillation. Boy did that baby make water in the Florida humidity. We were going to use PVC to replace it but the safety office said no way!!! I have used copper and love it.

Be safe out there,
JRW

gizmo2
08-18-2001, 06:17 AM
Tony, you can do the copper, I'm sure of it. Just try a couple practice pieces first, saw them apart and see how you did. Like others said, if you start with clean metal,well fluxed, you'll get good joints. If you're going to be in that location for any length of time, it will be $ well spent and a new skill you won't soon forget.

litman252
02-20-2006, 10:22 PM
Hello all,
I just bought a used air compressor and would like to run pipe up to the ceiling and over to the other side of my garage. I'm planing on using 3/8" hose at the end of the pipe for the misc. air tools. The simple question is do I need to use pipe bigger than 3/8" or not?? Pipe will be about 35' total, 50' hose on end.
Thanks,
Tony

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I'm Learning, have a long way to go

larry_g
02-20-2006, 10:44 PM
Tony
The simple answer is that you can. The complex question is how big is your compressor and what air tools are you intending to run with this system? Ifyour planning on running air hogs like D/A sanders, paint guns, big impact wrenches then you may be lacking. Air rachets, filling tires, etc. you'll be fine. If your air compressor is 110 volt you'll be fine. If you've got a real 5 horse machine that can deliver 12 scfm or more then you'll be lacking. Whatever you do, do not use PVC pipe unless its rated for air service.
lg
no neat sig line

3 Phase Lightbulb
02-20-2006, 11:07 PM
If you want to have a lot of fun, go crazy and follow this shop air design guide http://bbs.homeshopmachinist.net//biggrin.gif I setup 4 air drops using this and I couldn't be any happier with them:

http://www.bbssystem.com/pictures/shopair.jpg

-Adrian

HWooldridge
02-20-2006, 11:07 PM
Use 1/2" black iron pipe from Home Depot, Lowe's or a plumbing supply. Easy to put together and safe.

coles-webb
02-20-2006, 11:31 PM
You will have a pressure drop over a distance the same as with electricity (you need larger sized wire the longer your extension cord). Ideally metal pipe is the best answer, but if you are going to use rubber hose, use 1/2 inch for the first 50 feet and then use 3/8 hose. Some people will have a smaller (5 Gallon) tank at the end of the 50 foot line and then hook up your other 3/8 line.

Mike

rsr911
02-21-2006, 12:03 AM
I use copper both at home and at work. At work I've got a 15HP Boge rotary screw with a chiller and separator, that's plumbed into 150' of 1.5" trunk line. Every 10' section is joined by a 1.5 to 3/4 T with the T facing up. A short length then goes up to an elbow then to a ballvalve, unused valves are capped for future use. By going up out of the trunk line I reduce moisture in the lines although the chiller/evaporator and separator leave the air 99.9% dry. I prefer copper because it's easy to install, repair, and splice into. My father used black pipe in his garage, just try adding a drop or fixing a leak, you've gotta take half the pipe down. I did the copper at work about 4 years ago, no leaks or problems in that time under heavy use. In fact if I had it to do all over again I'd do it exactly the same way but I'd do it in the winter instead of June! Sure is hot sweat soldering pipe 20' up in a warehouse in 90 degree weather! My drops are either 3/4 or 1/2 depending on the need.

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-Christian D. Sokolowski

suprdvn
02-21-2006, 09:39 AM
Anyone notice that the compressor pump in the picture above looks like a mans face wearing a goofy hat. http://bbs.homeshopmachinist.net//wink.gif

mike.a.henry
02-21-2006, 10:41 AM
suprdvn, Go outside and breathe deep for a while.

Wirecutter
02-21-2006, 12:42 PM
<font face="Verdana, Arial" size="2">Originally posted by suprdvn:
Anyone notice that the compressor pump in the picture above looks like a mans face wearing a goofy hat. http://bbs.homeshopmachinist.net//wink.gif</font>

It's actually Elvis, and if you watch closely, the lips move. He's sending secret messages to Big Foot, who is supposed to come by in the UFO. They're going to drop in on the Loch Ness Monster for dinner.

TECHSHOP
02-21-2006, 01:12 PM
I see the face!

Guess I need to call the VA Hospital and ask about my meds.

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Today I will gladly share my experience and advice, for there no sweeter words than "I told you so."

litman252
02-26-2006, 06:13 PM
Thanks guys, I only have 8.4 SCFM with my little compressor. I'm checking with a guy to see what his compression fittings are like for 1/2 pipe. For the small price I'm going to fun 1/2" any way. The only diffrence will be pipe thread or compression fittings. Most of my air needs are for mechanic work or running the cutoff wheel. Picked up a spring return hose reel today, still need to get the pipe and get started on it.
Thanks again,

Tony

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I'm Learning, have a long way to go

pockets
02-26-2006, 07:23 PM
Tony,
You're starting a cycle that will not end, as long as you draw breath. Design your air system for three times what you think you need. Before you know it, it will be inadequate. Been bit by that dog....

Best regards,
Greg B.

charlie coghill
02-26-2006, 07:48 PM
Litman look at using copper pipe and soldering the connections. I used 3/4" copper pipe. Been real happy and have not made any changes to the system in 7 years.

japcas
02-26-2006, 07:49 PM
I'm not trying to steal the thread but can someone explain why you shouldn't use pvc pipe for air lines. I have seen it done with basic pvc rated way over what air pressure will be on it but it was standard water pipe and some people have told me it shouldn't be done but they never can explain why it shouldn't be done. Can anyone enlighten the ignorant like me?

Mcgyver
02-26-2006, 07:55 PM
isn't that the stuff that tends to shatter into shrapnel if it lets go? i think that's why

barts
02-26-2006, 08:01 PM
You don't use PVC for two reasons:

1) if it shatters it's like shrapnel; it also doesn't show up on X-rays. Some failure modes include lengthwise shattering.

2) Some compressors have leaked oils that degrade PVC, making the above problem worse.

Go with copper. Easy to fix or alter, light and safe. Yes, it's a few more $$, but go for the safety.

- Bart

japcas
02-26-2006, 08:06 PM
I can understand that it shatters when it breaks but some pvc is rated to 600psi or more which is a lot more pressure than a compressor will ever put on it but I hadn't thought about the possibility of the compressor leaking some oil into it which could compromise it's strenght. Thanks for the explanation barts.

litman252
02-26-2006, 08:38 PM
Well the reason this less than really knowledgeable person wants to use steel is that I can't solder copper good enough to hold water yet alone 130PSI. :-) Once I look at these compression fitting's I'll make up my mind on what to use.

My old boss used PVC, thick stuff. It worked good for a couple of years, then it shatterd and scared the heck out of them. He now has black pipe.

Tony

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I'm Learning, have a long way to go

snowman
02-26-2006, 08:42 PM
I was just at home depot reviewing the price of pipe.

I thought Adrian was dumb for buying his pipe from home depot...I'm soo much smarter for buying it from a steel supplier.

Well, it's actually cheaper from home depot. Weird

Anyway, back to point. 1/2" black pipe costs .789 per foot (10 ft lengths), 3/4 costs .989 and 1 costs 1.289. For a 35 foot run, I'd just buck up the extra ten bucks and put in 3/4...and know that you wont have to replace it later.

-jacob

J Tiers
02-26-2006, 11:34 PM
<font face="Verdana, Arial" size="2">Originally posted by suprdvn:
Anyone notice that the compressor pump in the picture above looks like a mans face wearing a goofy hat. http://bbs.homeshopmachinist.net//wink.gif</font>

Hey, anyone who saw that deserves to see this too:

http://www.animationarchive.org/2006/02/media-artzybasheffs-machinalia.html

Duct Taper
02-27-2006, 10:41 PM
At our local high school auto shop a piece of equipment was being moved by the students and it bumped into the PVC air line. The line shattered. Nobody was hurt but the line was immediately replaced with steel pipe.

Maybe PVC can handle the pressure and maybe the oil doesn't affect it, but mechanically it is not safe.

bobw53
02-28-2006, 07:38 PM
&gt;&gt;Well the reason this less than really knowledgeable person wants to use steel is that I can't solder copper good enough to hold water yet alone 130PSI. :-)


Copper is really easy to solder, clean it with sandpaper, scotchbrite, wire brush, whatever.
Slop on some flux, get it hot, and touch the solder to it, done. However, buy the greasy kind of flux, that white non-staining paste crap they sell at Home Depot and in the soldering kits is pretty close to useless, you might as well glue the pipes together with elmers. As for heat if you have a oxy/acetylene torch, its a lot quicker than a $10 propane job. Just get it hot all around, and then concentrate your flame a bit away from your joint, in the direction the solder needs to flow, touch your solder to the joint, and presto.

I'm far from a pro, I've only plumbed the shop at work and previous to that had done very little soldering successfully. Just my expieriences.

We ran about 300 feet of 3/4 copper, and the only leaks were the result of the white pasty flux. If it does leak, its an easy easy fix. We didn't run drops, but a downslope on all main lines to drains and then pointed the outlets upward. We are also running a big dryer near the compressor.

Another plus of copper as opposed to steel, is that it is so easy to add another outlet, pipe cutter, add a T, solder and your done in 10 minutes, total cost of about 3 dollars.

railfancwb
02-28-2006, 07:59 PM
Air under pressure is more like steam than water. With water under pressure, since it won't compress, a tiny leak drops the pressure to atmosphere quickly. Air and steam both compress and store far more energy than water for the same gauge pressure. Steam and its superheated water also store temperature energy... Charles

irontoart
02-28-2006, 08:13 PM
I beleive PVC also degrades when exposed to UV light for long periods

GregC
02-28-2006, 08:24 PM
1/2 or 3/4" copper is the way to go. It last forever and has a working PSI rating of something over 1000PSI. Easy and cheaper to install than black pipe.

Last Old Dog
02-28-2006, 10:58 PM
<font face="Verdana, Arial" size="2">Originally posted by railfancwb:
Air under pressure is more like steam than water. With water under pressure, since it won't compress, a tiny leak drops the pressure to atmosphere quickly. Air and steam both compress and store far more energy than water for the same gauge pressure. </font>
For all you spud gun - potato cannon - starch launchers, we all know PVC must be severely de-rated for temps on either side of 73.4F. Whilst temps of 100F (de-rate by 50%) may be rare, shop temps down to the high 30's or low 40'sF may occur in many geographic areas. PVC under air pressure can GRENADE at the slightest provocation. The resulting shards are as destructive to the human body as exploding glass. And the remaining pipe flailing about will beat the c^#$ out of whatever it can reach.

Keep in mind, just because it is marked "SCHEDULE 40" does not mean it is pres rated, it MUST be printed on the pipe. PVC for compressed air is scary.

Copper is my choice, and a peripheral loop around the shop provides two feeds to any drop. A tank at the opposite end can act as an accumulator for short burst high volume demands.

Last Old Dog

Dawg is pretty sick, I type for him, please excuse my feeble efforts

ERBenoit
02-28-2006, 11:25 PM
Another plus to the copper, the pipe won't rust if you have, or get "wet air" as the B/I pipe will. If you have "wet air", rust flakes will eventually occur. Unless you have "dry air" the compressor condensate will start the rusting process for you. One of the last things you need is another source (B/I pipe)of rust flakes flying around in the system.

Consider your filter/dessicator locations also.