02-02-2022, 07:24 PM
(02-02-2022, 04:58 PM)K O'Connor Wrote: Hi Guys
Nominally, shiny leads should accept solder well, but the lack of oxidation, etc visible to our eye does not mean the surface is perfect.
In my kits and amps I use a lot of resistors that I bought a long time ago or in large quantities. I use steel wool to clean them before installing them, and advise in the kit notes to do so for all non-shiny leads.
The problem with lead-free solder is that the solder does not flow and fill as smoothly as leaded solder does AND the cooled joint is not shiny. You cannot tell visually that it is "good". The same goes with silver solder, which to me is a complete waste of money.
The carbon footprint and related pollution of all kinds is much worse for lead-free solder than for leaded solder. There are specific minerals that must be added for lead-free solder to flow and to wet in any manner close to "real solder" - hehe. Lead is extremely bad for everyone and its limited use benefits everyone. However, for reliable solder joints you can't beat it.
You can brush on rosin with a little "acid" brush, just like in olden tymes. Rosin-core solder provides just the right amount for each connection and saves a step. Remember to let the joint cool and remove the dried rosin mechanically instead of chemically, as stated previously and elsewhere.
Have fun
Cheers for the info, much obliged