new batch of ww problems

[hornsurgeon]

i got half a pail of brand new never used wheelweights for on big rigs. i went to smelt them and got a suprise. they didn't melt like a normal wheel weight. they got very grainy and like wet cream of wheat before melting. when i poured the ingots, they took quite a while to harden. one was not quite cool enough, and actually broke when i poped it from the mold. the inside was very grainy looking, like pot metal. after they were cold, i took a piece and tried to shatter it with a hammer. i ended up flattening the ingot halfway, and no cracks or pieces. what do i have here?

[leftiye]

Probly lead contaminated with zinc is my guess. The stereotype that I got that was contaminated produced an oatmeal slush that would remelt if gotten hot enough. The printer had obviously been reusing it even though it was contaminated. You might still be able to cast it, I don't know. The slush when skimmed off of mine acted like that, though it was probly much harder. Sorry for the bad imput.

[xr650]

I've had ingots break with grainy look when not quite set up. 6 banger sprues will break with a grainy look when I throw them back in the pot fresh off the mould. They seem to cast OK though.

[kooz]

Just curious, what temperature were you smelting at ?.

[hornsurgeon]

not real sure, was over an open fire.

[randyrat]

I know 95+% Zink you can hardly cut or even sliver it with a blade it's very hard. If you can hammer this stuff flat chances it's not zink unless you got one or a couple zink wws in there to contaminate. Best test is cast it and see if it is castable.WWs look kinda funny when they are in their inbetween stage just before a molten state. (someone help me with the spelling here, it's a Eutectic metal) You may be OK

[JIMinPHX]

Sometimes WW are a little slushy & grainy when you smelt them if you don’t get them hot enough. I have been told stories that the truck WW have a higher antimony content, so that may be adding the difference. A little more heat & a little more fluxing may be in order. Of course, you want to stay below the melting point of zinc. I think that you need a thermometer or a temp stick.

[cbrick]

Let's see,

they didn't melt like a normal wheel weight. they got very grainy and like wet cream of wheat before melting.

Without knowing the temp of the alloy this is possible, I've done it myself and it looks just like silver oatmeal floating on the melt but it fluxes back into the melt readily and easily once complete liquidus it reached. Every metal in the alloy has a different liquidus temp with antimony the highest and last to become completely and fully liquid. What flux are you using and how long did you flux? Did you try to flux it back in?

when i poured the ingots, they took quite a while to harden.

The hotter the alloy the longer the ingots (or boolits) will take to cool. The larger the ingot the longer the center of the ingot takes to cool also and it will break and look just like you described if dumped too soon.

one was not quite cool enough, and actually broke when i poped it from the mold. the inside was very grainy looking, like pot metal. after they were cold, i took a piece and tried to shatter it with a hammer. i ended up flattening the ingot halfway, and no cracks or pieces.

Sounds just like lead when cooled just past the sludge stage and dumped from the ingot mould, when cooled and hit with the hammer and there was no cracking is also just what lead would do.

what do i have here?

From your description my guess would be . . . . Wheel Weights.

I HIGHLY recommend investing in a thermometer. Some on this forum think a thermometer is a waste of time but you could figure out what's happening or just go on guessing, your choice.

Rick

[Ken]

I smelted some linotype last week that acted a lot like that.
I would say try casting some bullets with it and you will have your answer as to whether its good or not.

[Huntducks]

add pure lead and see what happens

[hornsurgeon]

as it was only 45* here when smelting, i think the alloy was not as warm as i thought. i think i will be ok with these. no chance of any zinc ww melted, as these were all the same, brand new ww, never used. you should have seen the size of these ww. about 12" x 1" x 1/2". huge!

[bpost1958]

I've had the same thing happen. Adding pure lead to the pot at about a 10% rate helped a lot. I would guess it was the high antimony causing the issue. I like to use higher temps when casting with 6 cavity mold. It make the sprue separate better. It also does not smear lead across the top of the mold.

My .02

[hyoder]

I believe cbrick is right on.
If you get the melt to the slushy stage you cand gradually add heat until you just have a smooth melt and all the junk skims off nicely.
You MUST have a thermometer!