[TowerTalk] Silver Solder

Kevin Kidd kkbroadcastengineering at gmail.com
Fri Aug 7 13:48:56 EDT 2015


I would highly recommend that you use the silphoz brazing alloy IF you have
a torch hotter than a normal Mapp gas unit.

Silphoz is an alloy pioneered by the HVAC industry that is principally
copper with 5-15% silver and phosphorus.  It is self fluxing and will flow
on any reasonably clean copper without flux.

Traditional silver solder MUST be 40%+ silver to standup long term below
grade AND has to be carefully cleaned and fluxed AND is significantly more
expense for 40%.  Silphoz will last as long as the base materials at 5%
underground since it is mostly copper.  We use 15% silphoz for AM work
since it seems to flow better under most conditions.

It DOES require flame temps higher than a simple Mapp gas (or what passes
for Mapp gas these days) torch.  Wire to wire can be brazed with a simple
Mapp gas torch but anything larger requires Mapp/Oxy or Acet/Oxy.

Silphoz is sold under names like:  StaySilv, Silvaloy, Sil-Fos at most any
HVAC or welding supply store.  I buy it by the 25 pound box at somewhere
around $90/lb for 15%.  5% is somewhat cheaper.  40% silver solder is
significantly more expensive.

HomeDepot and Lowes probably has small qty packs of 5% for a significantly
higher per stick price than bulk but that may be cheaper than buying a full
pound.  A full pound will do a LOT of connections.  We typically only use
2-3 pounds per AM tower with 240 radials and copper strap.

In a pinch, you can use common fluxed brass brazing rods but they require
even higher heat.  If you are brazing to steel, you should use regular
brass rods...

Good luck,



On Fri, Aug 7, 2015 at 11:24 AM, mike stokes <mike9v at gmail.com> wrote:

> I need to improve my radials and lightning protection.  What Silver Solder
> is best for the job and where is a good place to purchase it ?
>



Kevin C. Kidd, CSRE/AMD
AM Ground Systems Company  -  WD4RAT
kkidd at kkbc.com  --  866-22-RADIO -- 866-227-2346
www.amgroundsystems.com


On Fri, Aug 7, 2015 at 11:24 AM, mike stokes <mike9v at gmail.com> wrote:

> I need to improve my radials and lightning protection.  What Silver Solder
> is best for the job and where is a good place to purchase it ?
>



Kevin C. Kidd, CSRE/AMD
AM Ground Systems Company  -  WD4RAT
kkidd at kkbc.com  --  866-22-RADIO -- 866-227-2346
www.amgroundsystems.com


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