On 11/30/2011 7:49 PM, John McGaw wrote:
> On 11/30/2011 7:30 PM, Grinder wrote:
>> On 11/30/2011 2:20 PM, John McGaw wrote:
>>> On 11/30/2011 12:09 PM, Grinder wrote:
>>>> I'm finally getting to the end of a 2-lb spool of 60/40 0.05" (18
>>>> gauge?)
>>>> rosin core solder I bought from Radio Shack years ago. This time
>>>> around,
>>>> I'm considering:
>>>>
>>>> * 63/37
>>>> * 0.032 (21 gauge?)
>>>> * Water-soluble rosin core
>>>>
>>>> Frankly, I'm enough of a hedonist that I'm happy to use as much lead as
>>>> needed to make my life easier.
>>>>
>>>> I do mostly circuit board repair, and some PCB prototyping. Any
>>>> opinions or
>>>> recommendations as to what solder works the best?
>>>
>>> That sounds like a good spec and that blend is eutectic for tin-lead,
>>> the diameter is right for semi-delicate work and water-soluble flux is
>>> pretty much a given. I'm still using up a 2-pound roll of Kester 62/36/2
>>> (with silver) which I first got decades ago when I was fixing Tektronix
>>> test equipment which called for it at the time and I'm getting old
>>> enough that more solder purchases seem unlikely.
>>
>> What does that bit of silver do for the joint?
>>
>
> Very little in most circumstances except that it probably conducts
> slightly better than regular tin/lead. Tektronix, back in the dark ages,
> used a method of construction which depended on ceramic 'sticks' with
> silver fired onto them to produce ultra-high impedance low capacitance
> circuitry. Other components were soldered onto the silver patches on the
> ceramic and silver in the solder prevented it from literally dissolving
> the fired silver and weakening the bond. All very high-tech back then
> but obsolete long ago. This type of solder is sold now for use with
> components having silver-plated leads but those are pretty rare. So
> there I was with this roll of expensive solder when my old 2-pound roll
> of regular stuff got used up so rather than waste it I started using the
> odd stuff. I use so little now that it will surely outlive me.

Would you be willing to include me in your will?