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Re: It is now time to plumb the garage for air.

To: "Shop Talk" <shop-talk@autox.team.net>
Subject: Re: It is now time to plumb the garage for air.
From: <jblair1948@cox.net>
Date: Fri, 10 Sep 2004 14:36:03 -0400
> Having replaced the air-less oil-less with a real two 
>stage....

>I'm now going to plumb the attached garage and basement 
>woodworking shop for air. The options appear to be steel 
>pipe, copper tubing or this new fangled TransAir stuff.

Arvid,

As others have said, you can run just rubber hose. Which is 
what I've done for years.  However, the pressure loss is significant.  I 
couldn't undo most the lug nuts on the cars 
in my driveway due to the line loses.

Quoting from my article on "media blasting" on my Morgan web page 
(http://www.team.net/www/morgan/tech/blasting/mediablast.html)

"Most compressors will come with 1/4" air line. Do yourself a favor and throw 
that away. Purchase some good 3/8" rubber hose (not the orangish plastic hose - 
it is very hard to work with when the temperature is below 60 degrees F.). 
There are line losses associated with both the diameter and length of the air 
hose, similar to electrical wiring. For an example, at 90psi a 1/4" hose will 
loose 29#s over a 25' run, and 39#s over a 50' run; while a 5/16" line will 
loose 10#s in 25' and 16#s in 50'. In my garage, I usually have 50' of 3/8" air 
hose hooked to my compressor. When I need to work on a car in my driveway, I 
add another 50' of hose. So, no wonder I'm having problems with my impact 
wrench at the end of 100' of 3/8" hose! While the line losses should be less 
than 16# per 50' (the value for 5/16" hose), I'm probably loosing at least 24# 
with the 100' of line. I really need to plumb my garage so I can shorten my air 
hoses."

> I'm not impressed with having to cut and thread steel 
>pipe, plus the possibility of corrosion drops it to the 
>bottom of the list.

I just finished this project in my place.  (Only took me
20 yrs to do it.)  I used black pipe, and luckily had a 
friend in the construction business so he had the thread cutter, a "portaband" 
portable band saw for cutting the
pipe, and a very nice tripod clamp for holding the pipe while cutting and 
threading.

The biggest problem we had was sealing the joints.  I used
teflon tape, and that didn't work.  So after we had run over 
50' and 2 drops, we pulled it all down and redid every joint
with a pipe joint compound (about $10 per can - used less 
that 1/2 a can on the job).  However, I still have several 
small leaks.  I can live with them, but can't leave the 
compressor on all the time (never did before).

Don't remember what I got in the way of supplies, but over 
80' of pipe, about 12 90deg elbows, and 6 "T"s for a total of right about $150. 
 It took us about 5 evenings working 
from about 3 1/2 hr per night.

There is a heavy schedule copper that is supposed to work 
for this type of installation.  I think this would be easier
to work and cheaper in price than black pipe.

The water in the pipes should not be a problem for a very 
long time.  I also put 12" down pipes below the "T"s
where I put the quick connect fittings and put ball valves
on the bottom so I can quickly and easily drain the water and or air from the 
system.

On advantage of using the iron pipe or copper is the cooling 
you can get from it.  Rubber hose is an insulator so you 
can't really cool the air and extract any moisture.  Same 
goes for PVC.

Hope this helps.

John






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