[R-390] WTF What The Flux?

[Charles Steinmetz]

Gary wrote:

>I use Kester 186 for tinning parts and leads.  While it is 
>officially RMA Flux and therefore can be left without removal, it is 
>nearly as strong as RA Flux.

It may be as strong as the RA flux you can buy today, but today's RA 
flux is a pale imitation of the real thing, which hasn't been 
available in solder cores since the early '80s.  Today's RA doesn't 
work as well as the RMA that was available in the '70s.  I buy up all 
the '60s/'70s RA solder I can find for this reason.

Some brands of new liquid RA flux (in bottles) still work like real RA flux.

Best regards,

Charles