Little Help on Lino Mix

[Nomadicone]

I've been casting since the mid 80s and I don't ever recall using lino in a mix. Little background then a question or two. As stated in an earlier post I needed to harden up some stick-on wheel weights. I melted them down a couple of days ago and sorted them using side cutters to test for zinc as well as keeping my pot around 600-650. Today I remelted the lead and added Linotype and mixed but had a scum floating on top so skimmed it off and fluxed.

Question 1: Any idea what that is or is it normal?

When I repoured the ingots and dumped them out one ingot broke in half and I noticed two ingots had about a 1/3 glossy surface and the other 2/3 of the ingot looked frosted.

Question 2: Did I fail to get the two metals mixed well or can anyone tell me what is going on?

 

[hornetguy]

I don't know... usually the shiny vs. frosty issue is a temperature related thing, in my experience. When pouring ingots, if you start with a cold mold, the ingots can have different appearances as it fills and heats up.
If you fluxed thoroughly, and all you had was a thin scum on the top, you probably had it mixed well.
It is also imperative to wait to flux until your melt is at casting temperature.
What do you use to flux? Just my own curiosity..

 

[Nomadicone]

I used Brownell Marvelux.

I'm guessing the glossy vs frosted is not related to temp as it was all in the same ingot but just two ingots had that discoloration.

 

[snuffy]

Well, when you skimmed and THEN fluxed, you removed some precious tin and antimony. You should flux THEN SKIM. The melt was probably not hot enough, causing the antimony to not be hot enough to alloy with the rest of the melt. If you still have that stuff you skimmed, add it back in, try re-melting it at around 800 degrees, then fluxing.

 

[Nomadicone]

Thanks snuffy. Perfect fix, I'll do that.

 

[crowbeaner]

I tried Marvelux just once; it stuck to the pot, ladle, and any thing else it came into contact with. I'll stick with beeswax, thanks. I generally use 50/50 lino to pure soft lead. This gives me an alloy around 7 1/2% antimony with just enough tin to facilitate band fillout. It also works very well if you make your own shot; it is harder than Lawrence Magnum at waaay less cost.