newbie....casting and zinc - again!!!

[wfsdno]

Okay, I've been poking around here for a few days and decided to join.

If I may ask a couple questions.....

I was melting some wheel weights and found one that didnt melt quickly, so I pulled it out. Then I found one that was slow melting (compared to the rest), got it out before much melted, it was sparkly metal (tech term here in MO). Panicking, I stopped melting that batch and poured into molds. Then I got curious, remelted that batch by itself and poured some bullets...guess what, they molded fine and all weighed the same as all my others!! Does that mean no zinc??

Second, what are your thoughts on battery cable ends? The part that hooks onto the battery. IF okay, what about the plastic molded inside??

Thanks again! Roger

P.s. Just as a bit of info, I've been casting my own lead balls for muzzleloading for years using pure lead, just now getting into boolit casting for smokeless powder.

[billyb]

did the suspect weight have a zn on it? if not it is probly ok i use the battery ends when i find them. the plastic melts. some of the weights are polamer coated making them look sparkley. do a google on wheel weights, the makers have info on thier products. Bill

[wfsdno]

None had 'ZN'. I look at them just to make sure. The sparkly was the inside of the W/W.

Roger

[HeavyMetal]

here's how it usually works, if it's lead it melts if it's not it floats!

Pull anything that floats! Now to be fair if your lead pot is down a quarter and you add some clip on ww's they will float until they come up to temp and melt.

The real trick here is to spot the zinc stuff before it hits the pot. A visual check will spot most of the zinc, it will look "different"! Pull the strange ones and then compare by weight against one of the same size.

Most ww have the weight printed on them so if you have one that says 3.5 oz and one "the same size" that says 1.2 oz I'm thinkin that would be zinc!

I realize that most are so dirty you won;t be able to read them but you should be able to "feel" the weight difference at least in the larger ones!

I've also chucked old battery terminals into my smelting pot, treat them like pure lead! Any metal inserts will float and you can skim them off and plastic will just melt and stink!

I think you got the zinc out before it became a problem. It's allways better to err on the side of safety, or in this case zinc, and pull any ww you think might be bogus rather than risk a contaminated batch of lead.

If they cast fine no issues.

[monadnock#5]

Get yourself a pair of cheap Chinee compound leverage tin snips. Use them to test any suspect weights. If you can cut into the weight easily with one hand, it's good to go into the pot. A weight that requires two hands to cut is bad news.

[wfsdno]

That is interesting, will avaiation shears work? I will try!

Thanks guys! Roger

[454PB]

The "sparkly" you saw is caused by the crystalline structure of the antimony in the wheelweight. In my 37 years of using WW alloy, I've yet to find one made of zinc. I've found a lot of steel ones and the stick-on type, but no zinc. I recently acquired two buckets of fairly new WW and expected to find some, but did not.

Zinc melts at 787 degrees, so you should keep your smelting temperature around 700 degrees. If you have a zinc weight, it will be obvious. Since zinc is lighter and melts at a higher temperature, any zinc weight will float on top and refuse to melt.

[Down South]

I just dump all of my WW into my smelting pot and fire it up. I do pick out all of the stick on weights and suspicious WW when I see them. I do have a thermometer now but I’ve smelted a lot of WW without one. I keep a close eye on my pot as it’s coming up to temp. Once all of the lead WW has just melted any zinc WW will be floating on top with the clips. I find zinc WW in just about every batch here. I think that I counted 9 of them in one batch a couple months ago. So far non of my melt has been contaminated with zinc.

[DLCTEX]

Search in this section for a thread titled "Wanted: Contaminated lead" to see testing I did with suspect lead and contaminated lead. Zinc will float on the melt for a good while before melting, and will remain seperate on the surface in a raised bead that has to be stirred into the lead. The zinc will continue to try to seperate, rising to the top to form a slush on the surface. Many weights were iron and were riveted to the clip. Some of the stickons were iron, also.Of course, they float. DALE

[AllanD]

Like I've said before Zinc is actually added to lead during the refining process..

Why? because the silver usually found in lead ores is something like
3000times more soluble in zinc than it is in lead and silver is commercially
worth seperating from lead.... not to mention that semi-refined lead is actually one of the better places to find gold (many lead ores contains more gold than the lowest commercially viable to mine gold ore)

Look up something called the "Parkes process" which is used to seperate solver and gold from molten lead.

The process depends on the fact that molten zinc will seperate and float on molten lead.



AD

[Tom Herman]

The "sparkly" you saw is caused by the crystalline structure of the antimony in the wheelweight. In my 37 years of using WW alloy, I've yet to find one made of zinc. I've found a lot of steel ones and the stick-on type, but no zinc. I recently acquired two buckets of fairly new WW and expected to find some, but did not.

Zinc melts at 787 degrees, so you should keep your smelting temperature around 700 degrees. If you have a zinc weight, it will be obvious. Since zinc is lighter and melts at a higher temperature, any zinc weight will float on top and refuse to melt.

Hi 454PB and the rest of the gang,

I'm starting to see Zink wheel weights here in Western Washington state.
What I do is to melt them a handful at a time. That keeps the temperature low, as they are always just melting, and I can skim off the steel clips and look for WW that float and don't want to melt. Those are pulled out likkedy-split!
So far, in about 200 pounds of WW, I've found about 2 pounds of Zink WW....
As far as Zn becoming more predominant than Pb, I don't know... Yes, all metals are sky high right now, but it seems like Pb is in less of demand than Zn is, as Zn has a crap load of more uses industrially, so the price should be higher for it.
So, if economics rules, we should have Pb WW for a L-O-N-G time, unless the environmental communist SOB's (like WA state government) demand the lead be eliminated.

-Tom

[wfsdno]

Thanks Guys, I use a small Lee pot, probably the smallest they make. I can only put in 3 or 4 at a time and let melt. Usually takes 30 seconds to melt the weights. I did find one that did not melt as quick as the others so I took it out. Did not keep it, now wish I did just to check it.

Thanks for all the help and posts!

Roger

[docone31]

Pretending to not be ignorant, what does zinc do in a batch of lead? I would think it would increase the hardness.
I melted about 20lbs of jewelery pot metal. I was thinking of adding some when the batch got low enough.
Any comments?

[Down South]

Pretending to not be ignorant, what does zinc do in a batch of lead?

It ain't good. Do a search on Zinc and happy reading.

[ra_balke]

Hummm...
Zink huh ?
I just ignore it, and use it anyway.

ya,, I know.

I keep my moulds really clean, I use a #2 pencil and pencil in the sharp corners of the mould, then, I smoke the mould with a wood kitchen match, then,,,, I get the mould good and hot.

Then I cast zink bullets.

I suppose I would not use them in a match, but they seem to work fine in 38 pistol. Sometimes they come out a little deformed, so I visually inspect them, and toss out the bad ones.

I wouldn't deer hunt with them in my 30 30 .

Well, that is my take on Zink in ww lead. And I have cast 100 k bullets in the past 35 years.

[docone31]

Well, I looked up Zinc. I guess from the reading, it is a good idea to keep the Zinc contamination to the best minimum a person can.
According to the article I read, it stiffens up the lead so it doesn't obturate well. That prevents a good seal down the bore.
Also, Zinc does not alloy as well as tin. It will float on molten lead especially if long melt times are used prior to casting.
Learn something every day. I found the info on the LASC site. They did considerable testing with different alloys.