In AM broadcast practice, I'll use 15% brazzing rods and a Oxy-MAPP torch. Some of my older stations have Cu strap in the dirt that is THICK, takes a lot of heat to flow on it.

I've melted in two some radial wires (soild #10 Cu) in the past with that torch, but they were aged wires and I was really throwing the white fire to them.

My experience, the paste fluxes always leave a lot of green oxide on the top of the copper -- likely not an electrical detriment, except for later additions, repairs, modifications, and aesthetics.

Good thread!

     - Josh / KF4YLM

On 10/12/2016 17:44, Drew Vonada-Smith wrote:

MAPP gas and a small torch doesn't pose much of a threat to pure copper.  I've 
never had an issue, and I am not particularly skilled.

A few asked me about sources for Stay-Silv 15.  Here is one example link from 

Those 7 sticks are enough to cross a lot of radials.  I might have used 2/3 of 
that for an entire four square with ground level radials.  If you want to use 
flux, helpful but not critical, the appropriate one is the Stay-Silv white flux.

Something like this works just fine for a torch.  It is also big enough for 
larger copper strap, braid, ground rods, etc.  Very useful.

Drew K3PA

Message: 10
Date: Wed, 12 Oct 2016 14:56:10 -0500
From: Matt Murphy <>
To: Drew Vonada-Smith <>
Cc: "" <>
Subject: Re: Topband: Soldering radials?
Content-Type: text/plain; charset=UTF-8

Is there any danger of damaging stranded copper wire by overheating it with
a torch when soldering or brazing?

Matt NQ6N

On Wed, Oct 12, 2016 at 2:41 PM, Drew Vonada-Smith <
Radials are a lot of work to put in, and the expense of wire is
significant.  I can't see any justification for not joining them the best
way available.  IMHO, silver brazing.

I use and recommend Sta-Silv 15 (15% Ag, 80%Cu, 5% P brazing stick) and a
simple MAPP gas torch.  Propane is not quite hot enough to work well.
Liquidus is 1475F.  Flux didn't seem necessary, but you could use white
brazing flux.  Sure, I spent $25 in solder over about 5 verticals, but of
what significance is that compared to the rest of the effort, to insure a
lasting joint?

Sta-Silv 5 is probably fine also, with a 1500F liquidus,  But I prefer the
characteristics of the 15%.  Very easy to work with.

Drew K3PA


Message: 5
Date: Wed, 12 Oct 2016 08:52:40 -0700
From: "Richard (Rick) Karlquist" <>
To: "" <>
Subject: Topband: Soldering radials?
Message-ID: <>
Content-Type: text/plain; charset=utf-8; format=flowed

I'd like to get the latest thinking from the group
on soldering radials.  What I currently thinking
is as follows:


1.  Tin lead doesn't hold up in the weather.

2.  "Stay Brite" 3% silver solder (97% tin,
no lead) is known to work well, but is expensive,
and has a considerably higher melting point
than 63/37.

3.  Lead free plumber's solder obviously works
in water pipes, but does it hold up outdoors
in the rain?  What is the melting point?


1.  Pure rosin.  Hardest to work with, but minimum
corrosion issues.

2.  Activated rosin.  Easier to work with.  What
corrosion issues are there?

3.  Acid core plumber's flux.  Very easy to work
with, very corrosive.  Does this hold up in the
rain, etc?

(I remember the dire warnings that Heathkit manuals
had about not using acid core solder, but I
guess that doesn't apply to radials.)


Has anyone tried crimping as an alternative to solder?



Subject: Digest Footer

Topband mailing list


End of Topband Digest, Vol 166, Issue 8
Topband Reflector Archives -

Topband Reflector Archives -

Topband Reflector Archives -

Reply via email to