Newsgroups: rec.crafts.metalworking
Subject: Re: Flux for silver solder?
From: kimberln@crl.com (J. Kimberlin)
Date: 21 Feb 1995 17:56:25 -0800

In article <3idi0v$ooc@aimnet1.aimnet.com> kopfj@aimnet.aimnet.com (John O. Kopf) writes:
>In article <3icq7c$e0o@cambridge.village.com>
>richer@cambridge.village.com (Al Richer) writes:
>
>> What IS silver solder flux? Borax? -ajr
>
>A reasonable approximation is grovery-store borax, wetted with boric
>acid (eye-wash) from the drug store.

Seems to me that this would work OK.  Generic borax is sodium borate and 
acidifying it with boric acid would be logical.  

Some silver solder fluxs are sodium fluoborate, however.  These contain 
fluorine and carry a warning on the label "contains fluorides."  Probably 
good for getting under glassy oxides such as those on silicon and 
aluminum bronze which are normally difficult to silver solder using 
ordinary borax flux.

JerryK