[T3] Air compressor ?

William Jahn willjahn975 at gmail.com
Sun Jul 26 20:21:40 PDT 2020


Both the old and new copper pipe walls measure .040"

On Sun, Jul 26, 2020 at 6:27 PM Mike Fisher <fisherfarms at gmail.com> wrote:

> Force a tapered steel punch down it to get it round again.
>
> On Sun, Jul 26, 2020 at 6:21 PM William Jahn <willjahn975 at gmail.com>
> wrote:
>
> > The tube I got is a replacement and it's the same wall thickness as the
> > original. The only issue I see is for some reason the tube is not
> perfectly
> > round . It is 1/2" OD and 3/8" ID . The leak is not real bad yet I'd
> prefer
> > there were no leaks. The Unloader releases the head pressure. I don't
> need
> > the head to check valve tube to help out.
> >
> >  If I could just take a 3/8" drill bit shank or whatever bit that fits
> and
> > tap it in 3/4" it might round the copper and create a seal between the
> > ferrules and copper tube. Since the ferrules are in place they would keep
> > the OD of the copper from expanding. I don't really want to try to
> tighten
> > the fittings more and end up with a ferrule that collapses the OD of the
> > copper like the very old original one was at the head end. I bought a new
> > 1/2" compression fitting because I needed the nuts and ferrules I could
> use
> > the body , fit the new pipe with the ferrule then try to fit a 3/8" drill
> > bit shank  in to make  certain the ferrule remains round. I would smooth
> > the bit and taper the end a bit more and lube it so as not to destroy the
> > inside of the copper.
> >
> >  As is livable it's better than before. The new replacement copper is
> > really tough to bend like the old one was. I tightened it finger tight
> then
> > 1/2 turn more and it leaked and gave it another 1/2 turn same thing. This
> > was what I found on you tube sites. I normally finger tight then use a
> > wrench till it feels snug and never crushed the copper or had leaks. The
> > original tube at the head was tightened so much that the ferrule was
> barely
> > more than the copper OD and I could see the ferrule past the nut. I never
> > noticed this until I replaced the check valve and the check valve end was
> > fine . The fellow I traded for it might have cranked down on the heads
> > fitting to cure a leak. I know the new copper is not round yet it
> measures
> > the same OD as the original . Once I realized it leaked I removed it to
> see
> > why and found the ferrule made contact all around except one small area
> . I
> > doubt more tightening will help.
> >
> >  This stuff drives me nuts when you get a new pipe and find it has a
> small
> > flat spot and I slide a new ferrule down the entire pipe and it has that
> > slight flat spot the entire length.
> >
> >
> >
> > On Sun, Jul 26, 2020 at 5:44 PM Jim Adney <jadney at vwtype3.org> wrote:
> >
> > > One thing to keep in mind is that copper tubing comes in different wall
> > > thicknesses. The thinner wall stuff is not suitable for any of the
> > ferrule
> > > style
> > > sealing methods, because the wall will just collapse rather than being
> > > stiff
> > > enough for the ferrule to bite into it and seal.
> > >
> > > I learned this lesson many years ago, when i was working on a small
> > system
> > > that had to be helium leak-tight. I could make a leak tight joint at
> one
> > > end of
> > > the tube, but as soon as I did ANYTHING to the other end, the movement
> > > would open up a leak on the first end. The thing I was working on was a
> > > network of maybe 20 connections in a couple square feet, so until I
> > > switched
> > > to heavy wall copper, I was just chasing one leak after another.
> > >
> > > I finally found recommendations from Parker and Swagelock regarding the
> > > min. wall thicknesses for various diameter tubes that could be reliably
> > > sealed. Look here:
> > >
> > > https://www.swagelok.com/downloads/webcatalogs/EN/MS-01-107.PDF
> > >
> > > Read the section about gas service on page 2, as well as the chart on
> > page
> > > 7 regarding copper tubing. The note at the bottom of page 7 seems to
> > > indicate that the minimum wall thickness for air in 1/2" copper tubing
> > > would
> > > be 0.049".
> > >
> > >
> > > --
> > > *******************************
> > > Jim Adney, jadney at vwtype3.org
> > > Madison, Wisconsin, USA
> > > *******************************
> > >
> > > _______________________________________________
> > > VWType3.Org mailing list - type3 at vwtype3.org
> > > To unsubscribe or change subscription options, visit:
> > > http://lists.vwtype3.org/listinfo.cgi/type3-vwtype3.org
> > > If you need more help, contact: gregm at vwtype3.org
> > >
> > -------------- next part --------------
> > An HTML attachment was scrubbed...
> > URL: <
> >
> http://lists.vwtype3.org/pipermail/type3-vwtype3.org/attachments/20200726/bbe97228/attachment.html
> > >
> > _______________________________________________
> > VWType3.Org mailing list - type3 at vwtype3.org
> > To unsubscribe or change subscription options, visit:
> > http://lists.vwtype3.org/listinfo.cgi/type3-vwtype3.org
> > If you need more help, contact: gregm at vwtype3.org
> >
>
>
> --
> Eugene, Oregon
>
> http://s169.photobucket.com/albums/u236/mr_bojangles500/
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL: <
> http://lists.vwtype3.org/pipermail/type3-vwtype3.org/attachments/20200726/9c8176e7/attachment.html
> >
> _______________________________________________
> VWType3.Org mailing list - type3 at vwtype3.org
> To unsubscribe or change subscription options, visit:
> http://lists.vwtype3.org/listinfo.cgi/type3-vwtype3.org
> If you need more help, contact: gregm at vwtype3.org
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.vwtype3.org/pipermail/type3-vwtype3.org/attachments/20200726/d2d707c3/attachment.html>


More information about the type3-vwtype3.org mailing list