AC 50/50 hardness question

[kelbro]

What are you seeing for hardness with AC 50/50 WW/Pb?

I have some that were cast this past weekend that measured right at 8.0. Pulled a batch that was poured 1 1/2 yrs ago and it measured 10.0.

Is it possible that it ages up 2.0 BHN or is it just a WW lot variation?

[onesonek]

I haven't used that blend. But I do know it could take as much as 3 weeks or so to age harden, ( maybe more), where you will get s closer reading. And then they will continue to harden some over time. Then again, it is possible to see some variation, but not likely 2 points, unless your base metal's are quite different. Mostly, you haven't given it enough time. Check them after 3-4 weeks.

[geargnasher]

7-9 the next day, 9-11 after a few months. YMMV, depends a lot on WW composition, and what you're using for "pure". My clip-ons have been coming out 14-15 air-cooled lately, softest ones I've seen are still around 13 air-cooled and aged, conventional wisdom indicates 11 or so for a normal WW number. I mix roofing lead, shower liners, sewer pipe joints, and the really soft stickies as my other 50%, which isn't pure lead but soft enough for my purposes.

Gear

[kelbro]

Thanks. After a little more checking, I'm pretty sure that both of these lots were from the same batch of clip-on/stick-on alloy that I brewed up in '09. I was just a little surprised at the 2 BHN increase.

[Larry Gibson]

7-9 the next day, 9-11 after a few months. YMMV, depends a lot on WW composition, and what you're using for "pure". My clip-ons have been coming out 14-15 air-cooled lately, softest ones I've seen are still around 13 air-cooled and aged, conventional wisdom indicates 11 or so for a normal WW number. I mix roofing lead, shower liners, sewer pipe joints, and the really soft stickies as my other 50%, which isn't pure lead but soft enough for my purposes.

Gear

+ 1.

Larry Gibson