Re: Merging copper tubing for Primaries

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Original poster: "Dr. Duncan Cadd by way of Terry Fritz <twftesla-at-uswest-dot-net>" <dunckx-at-freeuk-dot-com>

Hi Bart, John!

Date: 03 February 2001 17:13
Subject: Re: Merging copper tubing for Primaries


>I simply cut a piece of  wire (six gauge I think?) that
>formed a tight friction fit inside the tubing in order to
>join the two rolls.

<snip>

>If your soldering iron is not hot enough, and you don't
want to buy
>a propane torch.....you can solder it over a gas burner on
a kitchen
>stove, if you have a gas stove.  Or maybe a friend has a
gas stove (range),
>if you only have an electric stove.


I recall the ARRL doing tests on various beam aerials in
which the bits of tubing were secured together simply by
means of jubilee clips (exhaust clamps in American?) and
compared against more solid means of connection.  There was
no difference in performance.  Even when the clamps were
slackened off, there was no difference until things got
loose.  The tight fitting wire is thus probably quite OK.
If you really worry about this, you can improvise with all
manner of things.  I use an old camp stove run on methylated
spirits for the _big_ jobs (like soldering a couple of pound
lumps of brass together) and a 50 year old 225W thermostatic
soldering iron from Glendale CA in the good ol' US of A
takes care of the smaller stuff.  Pity I can't read the
maker's name or I could tell you where to look! Maybe you
could check out a local army surplus store and pick up some
of the fuel tablets they use for camp stoves.  One of those
tablets should be enough to join a couple of bits of 0,25"
copper tubing, no problem.  It'll take a while to heat up
enough for the solder to flow, maybe several minutes, and
having flowed, it will take another long while to cool back
down again.  Don't burn your fingers!  (Been there, done
that!)

Dunckx