[SEL] SEL Digest, Vol 79, Issue 28

[Jerry Evans]

At 06:00 PM 30/10/2010, you wrote:
>Message: 7
>Date: Fri, 29 Oct 2010 22:24:15 -0500
>From: "Bill Dickerson" <bill at antique-engines.com>
>Subject: [SEL] OT-OT- air lines in shop?
>
>I've got to get a better way to get air to my work benches and other areas
>instead of a single hose dragged all over the place from the compressor in
>the corner.
><Big snip>
>OK, finally the question - what are others doing?
>Is the copper pipe with solder/sweat connections ok?
>What about the M compared to L grades of pipe?

Hi Bill,
         Not sure what you guys in the USA call it but my airline is made 
from the thin walled drawn copper pipe used for plumbing and sweat soldered 
together (actually more like capilliary action soldering).

         This drawn (stretched ??) copper tube is much harder than the 
thicker walled (bendable) variety. My Compressor is under cover on the 
outside of my shop and I run an airline down both sidewalls (21 metres long 
each) as well as across the shop in 2 places (7 metres each) and also on 
various points outside the building. The long runs down the sidewalls 
should join at the far end to form a loop but I ran out of pipe before they 
met and have never got round to adding that last bit :-) but it would help 
to equalise the pressure.

         I have downpipes approx. every 1 1/2  metres apart (I'm a lazy 
bugger and don't want a long pipe or have to walk far to plug into air) 
with quick connect couplers . I've used 1/2" pipe throughout and my 
compressor is a Broom Wade (rather elderly but excellent quality) and is 
set to about 110 lbs/sq inch.   I have a loose pressure regulator that is 
also fitted with quick connect couplers and just plug this into whichever 
outlet I feel like using  at the time and set my pressure on that. By doing 
it that way the pressure on the line does not need to be changed for 
different purposes so I can for instance spray at quite low pressure and 
have another pipe about 1 1/2 metres away with high pressure for blowing 
dust away.

         I then have 4 or 5 compressor hoses of different lengths and can 
choose the one best suited to what I want to do.

         Regarding condensation - the answers already given are valid. Take 
the outlets "Up" out of the top of the pipe first and then bring them down 
to where your coupler is. The mains line must slope with a drain at the 
lowest end. (I have one on each corner of the building).

         This discussion was on the list about a year or so back and quite 
a lot of mention was also made of a cooling "device" near the compressor 
but I do not have that.

         My airline has been up since about 1988 and I've never had a leak 
or any other serious problem with it. My compressor is permanently switched 
on and, if I do not use any air then it only switches on about once in 3 
days - I think that the small amount of leakage is probably through the 
valves in the compressor. The only small problem is that the quick connect 
couplers on the outside walls are not brass and they tend to get a bit "dry 
and sticky" and need to be taken off every 2 years or so and oiled up and 
loosened and then they are fine again. (A bit of Q20 usually does the trick).

         My drains are not automatic - I blow them all out (and the one 
under the compressor) whenever I need to spray paint or use airtools. If I 
only need to use the blower I don't bother. Summer is our wet season and 
this needs to be done more often then due to the higher humidity in the air.


Keep the revs up (or down)
Jerry Evans
Near Johannesburg in Sunny South Africa.
Etched Brass Engine Plates made to order:
<www.oldengine.org/members/evans/plates/index.htm>