60/40 or 40/60?

[BHChieftain]

Sigh... too many *&%$ choices at the hardware store...

For solder, do I use 60% tin/ 40% lead rosin, or 40% tin / 60% lead or does it matter (I know to avoid acid )

Secondly, any problems mixing these on a joint? ( I was using 60/40 , but I need to rework, ok if I use 40/60 to supplement)

-Chief

[m4a1usr]

Use the 40/60. Its my preferred solder. You can mix the 40/60+60/40 if you have to. Solder with a higher tin content melts at a lower temperature. So the 40/60 is good and strong and the melting temp is low enough IMO (460degF). Just my 2 cents.

BTW, I prefer to use solid core. Why? Because I dont like the cheap brown rosin they inject into the center and because its solid a roll lasts forever if you buy it in a large enough diameter. I like 1/8th". And I buy a jar of greenless rosin paste, 4 oz container, and it lasts forever too.

John

[tth]

I agree with John. I use solid solder with paste.

[BHChieftain]

As always, thanks guys,
-Chief

[bigwaveohs]

As always, thanks guys,
-Chief

The details...
Tin/Lead Melting Point
40/60 460 degrees F (230 degrees C)
50/50 418 degrees F (214 degrees C)
60/40 374 degrees F (190 degrees C)
63/37 364 degrees F (183 degrees C)
95/5 434 degrees F (224 degrees C)