Too much dross?

[Markbo]

I am wondering if I am doing something wrong. I smelted up probably 120 lbs of ingots yesterday from wheel weights and thought I would cast some today. Beautiful outside... not too hot and all my chores are done.

Soooo... I melt about 12 lbs - all recovered wheel weights - in a cast iron pot and set to heating it up. Once liquified I drop in a couple tablespoons or so of wax as flux and stir it in. About 2 ladels of dross was skimmed off the top and I start casting.

About 50 or 60 bullets into it I notice that there seems to be a lot MORE dross... I don't know why. I drop in 2 more 3.5lb ingots and flux again... now I have another 2 ladels of dross to skim off the top. It is just gray 'fluffy' stuff that floats on top.

Is this normal or am I doing something wrong?

[Wally]

I am wondering if I am doing something wrong. I smelted up probably 120 lbs of ingots yesterday from wheel weights and thought I would cast some today. Beautiful outside... not too hot and all my chores are done.

Soooo... I melt about 12 lbs - all recovered wheel weights - in a cast iron pot and set to heating it up. Once liquified I drop in a couple tablespoons or so of wax as flux and stir it in. About 2 ladels of dross was skimmed off the top and I start casting.

About 50 or 60 bullets into it I notice that there seems to be a lot MORE dross... I don't know why. I drop in 2 more 3.5lb ingots and flux again... now I have another 2 ladels of dross to skim off the top. It is just gray 'fluffy' stuff that floats on top.

Is this normal or am I doing something wrong?

That fluffy stuf is zinc.... you have to cull the zinc WW's to prevent this before you melt them.

[Markbo]

that was done during the smelt. Anything not lead was skimmed off along with the old clips.

[Springfield]

Keep fluxing until it goes away. Everytime you put in a new ingot you will probably get more as all the impurities didn't go away during the smelting. Running the lead too hot will make it worse also.

[462]

I, too, suspect that there is some zinc contamination. Not all of them are marked Zn, and they can easily be overlooked.

[Wally]

that was done during the smelt. Anything not lead was skimmed off along with the old clips.

I had this happen to me---the fluffy stuff was zinc...

[243winxb]

Try getting the alloy hotter, see what happens.

[williamwaco]

Your alloy is contaminated with zinc.

You cannot "flux it away" with wax. It will keep coming back until the pot is empty.

Check this posting:

http://castboolits.gunloads.com/showthread.php?t=62957&highlight=zinc+contamination

PS, I find that fluxing heavily three or four times with sawdust will reduce it somewhat.
I did not have good luck with the sulphur suggestion.

The "less bad" news is that you can cast bullets with it. and they seem to shoot OK.