[TowerTalk] Lightning protection questions.

[Jim Lux]

At 02:16 PM 7/27/2004 -0400, Tom Rauch wrote:

> > What alloy are you using, Tom. Most of the stuff you can
>buy at
> > home box stores is for plumbing applications (96%Tin, 4%
>Silver).
>
>
>I've been intending to pull and invoice and look, but
>welding supply houses sell the correct materials. For small
>quantities (such as attaching taps on tubing coils for tank
>circuts) we used to buy solder from sources like Granger and
>McMaster Carr.
>
>When I eventually reorder some, I'll make a note of the
>exact material. The material I use is barely melted with
>Mapp gas, and uses a white paste flux. I'm sure it is also
>used in refrigeration applications.
>
>
>73 Tom

Just looking through page 3163 of McMaster-Carr...
Looks like there are cadmium containing and non-cad containing 
varieties.  Antenna work is probably outside in good ventilation, so the 
cad-containing kinds are probably ok.

The silver content ranges from 35-60%.  Since you're paying for the silver, 
you probably want the low silver, high copper alloys (so called High 
Fill)  35% Ag, 26 Cu, 21 Zn, 18 Cd.  Melts at 1125 to 1295...

The higher silver alloys (like 45%) melt a bit lower 1125 to 1145, and 
aren't much more expensive.

Then, there's things like silver/copper/phosphorus blends for brazing 
copper... 15/80/5 or 5/89/6... they melt at temps up to 1500F.