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OldBuckstalker1187
12-17-2010, 09:48 AM
I believe that I read somewhere that you can melt down pewter for its high tin content to mix in with your lead. I do have a question however. I have also read that some pewter has up to 3% copper in it and some has as little as .25%. Will this ammount of copper affect casting boolits and prohibit good flow to fill out your molds? If so, how can you tell which pewter has the 3% copper and which pewters have only .25% ?

358wcf
12-17-2010, 10:31 AM
I've been using pewter for several years with nothing but good luck- I treat it like the very tin-rich alloy that it is, making bullets from pewter to add to the pot to "sweeten" it with tin-rich alloy for better fillout. I've never found the other metals in pewter to cause any problems at all-
Enjoy-

358wcf [smilie=1:[smilie=1:[smilie=1:

Rangefinder
12-17-2010, 12:24 PM
+1 on that. I make mine into little coins--partly for the consistency of sweetening the same way every time, mostly because the kid in me likes having a giant bag full of shiny coins. But I've never had anything but wonderful results with any of my pewter sweetener. Have at it and enjoy the results.

mold maker
12-17-2010, 01:52 PM
See there,,, I've been wondering what to use, as a very small ingot mold, for pewter. Learned something else today, after casting for over 40 years.
this was one of those Duhhhhh moments.
You guys together, represent the biggest wealth of knowledge to be found.
Once more, Thanks Guys !!!!!

Rangefinder
12-17-2010, 02:44 PM
I've been wondering what to use, as a very small ingot mold, for pewter.

My "coin" mold is nothing more than a dozen or so soda cans flipped over. Poured level with the lip will give a consistent 4oz. coin. I pour 4oz and 2oz. That makes it really easy to calculate allow sweetening.

rob45
12-17-2010, 03:52 PM
Short of having the pewter analyzed, there is no easy way to identify copper content. There are many different formulas used for "pewter".
Using unidentified pewter is the same concept as using babbitt- we don't always know the exact composition, yet we still use it.
And tin-based babbitt can have anywhere from 3-8% copper in the most common alloys, so I highly doubt you're going to have any problems with your pewter.

Besides babbit, other antimonial alloys, such as typemetals, also have copper in them, but we successfully use them, too. Most alloys with antimony (yes, several pewter formulas call for antimony) will also contain copper, but, as a general rule, the only ones with enough copper to give us problems are the various babbitt formulas.

If we were only talking about pure lead and pure copper, the solubility of copper in lead is less than .15% at around 750F. Hotter means the copper content can be increased, cooler means less soluble.
Naturally, we're not dealing with just pure lead and copper; we're trying to utilize an already-made alloy for the tin content. But we can employ the same principle in our methods.

When I have something that I think may contain a high percentage of copper, this is what I do:
1. Melt the primary lead source (WW, range lead, flashing, whatever).
2. Add the tin source (pewter, babbit, typemetal, whatever).
3. Bring entire melt up to 750F. When it reaches temp, stir well, flux, and skim.
4. Bring temperature of melt down to about 625F. This may take some "fiddling" depending upon how well you "know your setup".
Pure lead melts at 621F, and all of the alloys we use melt even lower. The thing we're trying to accomplish is reduced heat to diminish the solubility of the copper.
5. Let the temp stabilize at 625. Do not flux or stir.
6. Carefully skim the top surface. Be careful to only remove the top surface; do not stir.
Sometimes it will have a lumpy appearance; sometimes it will appear to be a thin sheet layer. If lumpy, keep skimming until gone. If a thin sheet appearance, stop skimming because now you're taking out too much tin.
7. When lumps are gone, turn heat back up to desired pouring temp and flux. Don't forget to flux, because the top "sheet" layer is now primarily oxidized tin, and extra tin is the purpose of all of this.

I learned this procedure from an old Lyman handbook, and it works very well.

A special note on point 6:
The "lumpy" appearance of the top layer can also be viewed as a "mushy" appearance, dependent upon the alloys being used. What we are removing are actually intermetallic compounds, not just copper. So those compounds also contain tin, antimony, etc.
But the point to remember is that we are leaving far more of the stuff we want (tin) while taking out the stuff we don't want (copper).
By the time we reach a "thin sheet layer", enough copper has been extracted that it is of no detriment to us, plus the fact that we want to retain the tin, which appears as a "thin gray sheet" in its oxidized form.



Here are my rules of thumb concerning "tin-rich" alloys which may also contain copper:

Pewter- I don't worry about it unless it gives problems, and everything I have used to this point has given me no problems. (See final concern below.)

Type metals- most use these for the hardening properties of antimony, but many people also use them specifically for the tin. I have never had any "copper problems" with any of the type metals.

Tin babbitt- I always follow the procedure noted above.

Solder- The "common" and economical solders available to us have never given me problems.
Yes, there are many formulas for solder, but the ones that may give us problems are usually a)not commonly available as scrap, or b)not economical enough to be used as a tin source.

Unknown- Got something unknown a friend gave you? Purchased some "tin alloy" from evilbay, a garage sale, or somewhere else?
I make a small "test batch" and see what happens.


Conclusion: You're probably not going to have any "copper problems" using pewter as a source of tin.
The larger concern is using those rare "pewter" formulas which contain cadmium, much the same concern as using batteries for the lead.
These formulas containing cadmium are rarely used because most do not want to deal with the inherent problems; when they are used, it's mainly by jewelers. I have never heard of it being used in mugs, plates, etc.

I do have a friend that is a jeweler; here is an interesting link to one of his suppliers if you are interested in learning more about "pewter" content:
http://www.alchemycastings.com/lead-products/jewelry.htm

By the way, don't raid Grandma's heirlooms off of the mantel; she might threaten to leave you out of the will!;)

Good Luck,
Rob

fryboy
12-17-2010, 05:33 PM
much in the way of pewter i find is silver plated , while perhaps not true i like to think this imparts "anti werewolf properties" lolz , as rob posted ( excellent post amigo +10 ! ) copper is less a problem than something such as zinc , if one follows his link you will see that few alloys listed have much more copper than 1% , and while copper is harder than lead nickel is even harder than copper as is guilding metal , which if it was a problem then so would be melting down scrap range lead ( but it's not ) as for the pewter it's self , as noted the content varies , the best is marked with tin content , the best practice is to melt each pewter piece separately as this helps sort out troublesum and questionable alloys , using a lee tester i have had mixed returns regarding hardness but even with the most trying lead alloys i was using i have never needed to add over 2% pewter to ( just as with if straight and pure tin was added ) i also try to make large quantities of alloy to help keep variations of my casting at a minimum , one of my favorites i'm sure some will think a waste but i make both of lyman's # alloy recipes and then blend them at 50/50 it works for me but as always your mileage may vary ( FWIW ? once made i never have to add tin or pewter again to that mix lolz )

Zbench
12-17-2010, 06:20 PM
I routinely buy pewter stuff at yard sales and other places I see it. I wait until I get about 50# and then fire up a small pot and melt it all down into one big ingot. Once it's all molten, I stir and flux, and then pour a single 1# ingot.

I then take that ingot to the local scrap yard where they have an XRF analyzer. Since we do quite a bit of business there, they are always happy to shoot whatever I bring.

Today we dropped off some scrap for sale, and I took a couple ingots that I've had around from the last two batches. One turned out to be 85% tin and 5.5% antimony, the other 88% tin and 5% antimony. The balance was some lead, and lots of trace metals like iron, copper etc.

Bottom line, if it's stamped pewter on the bottom and you get enough of it, it should be in the range I mention above. If you have a scrap yard that is near you, you might try my approach. Nothing like really knowing!

Pete

OldBuckstalker1187
12-19-2010, 01:47 PM
Thanks alot guys, all of you are extremely informative. Im learning more and more each day.

arjacobson
12-19-2010, 05:46 PM
I started looking for pewter also. Wife and I hit all the goodwills/salvation armys/affordables. I ended up with a figurine-amedallion-and last but not least a 97% ZINN large plate.. Just turned them into small coin like ingots this morning!! Shiny!!!

kbstenberg
12-19-2010, 07:54 PM
Tomorrow the wife an I are going to a thrift store. That she found last week that had a matching set of dishes that are Pewter. The price is beyond my means but I figure someone here will snap it up from me. Wife said there were about 12 plates which includes a Large serving platter. Look for my thread Mon. or Tues.
Kevin

imashooter2
12-19-2010, 09:27 PM
Tomorrow the wife an I are going to a thrift store. That she found last week that had a matching set of dishes that are Pewter. The price is beyond my means but I figure someone here will snap it up from me. Wife said there were about 12 plates which includes a Large serving platter. Look for my thread Mon. or Tues.
Kevin

Be careful. A lot of the large plates and platters are Wilton Armetal which is not pewter even though sellers and stores mistakenly say it is.

1Shirt
12-19-2010, 09:35 PM
Got a slightly dented English Pewter that weighs about 2 1/1 lb. at a thrift store a couple of weeks back. I search out the dented presentation mugs with the glass bottoms that people give for going away, and usually sell for about a buck a piece.
They weigh about 8-9 oz minus the glass. I just make sure they are stamped from England.
1Shirt!:coffee:

onesonek
12-19-2010, 09:46 PM
Just curious from a learning standpoint,,,what problems occur when one might have too much copper in the melt?

imashooter2
12-20-2010, 12:41 AM
Just curious from a learning standpoint,,,what problems occur when one might have too much copper in the melt?

Spout freeze with bottom pours is one symptom.

a.squibload
12-22-2010, 10:51 PM
At a thrift store I found a bowl, about 10" dia by 4" high, less than a pound.
Beat, dented and scratched.
Marked $5, I asked for half price, no deal.
They think pewter is gold, nobody's gonna buy that bowl for $5, it was trashed.

Zbench
12-23-2010, 12:06 PM
Squib,

You might want to rethink your calculus. Tin closed at $12.20/lb yesterday. Considering you can't buy it for less than $14, at $5 for about a pound of pewter, that it less than half the going rate. I'd a bought it and added it to the crunk pot!

Pete

a.squibload
12-23-2010, 10:25 PM
I should have said "significantly" less than a pound, it was kinda thin.
'Course I didn't weigh it.
Mainly I was upset that they refused to haggle on that piece of scrap!

Rangefinder
12-24-2010, 10:54 AM
I know what you mean Squib---One of the thrift stores in my area is the same way. They have a vase there that probably weighs close to a pound. It's been hanging around there for several months and no one will touch it because it has a big dent in one side. But they still think it's worth every penny of the asking $15... I offered $5 and the lady said nope--$15. You can turn the dent to the wall and it looks just fine...

Whatever...

oscarflytyer
01-10-2011, 01:03 AM
Go look at the Rotometals web page. Check the Pewter tab on left.

R92 Pewter has 8% antimony in it! No tin.

lwknight
01-10-2011, 01:11 AM
The R92 pewter is 92% tin and 8% antimony.
How does that work out to be " no tin" ?

*Paladin*
01-10-2011, 08:33 AM
I just got two pewter goblets yesterday for $3.50 total. I haven't weighed them yet, but they should be about 1 lb each. They had a little candle snuffer for ~$5 that was pewter as well, but they wanted $7 for it, so it got left.

badbob454
04-02-2011, 06:15 PM
Go look at the Rotometals web page. Check the Pewter tab on left.

R92 Pewter has 8% antimony in it! No tin.


Alloy name Tin %
Antimony %
Copper %
Bismuth %

A/C- Pewter
92% 7.75% .25% 0%
R-92- Pewter
92% 8% 0% 0% .......................this has 92% tin you must have missed that !!
R-98-Pewter 98% 0% 0.50%
1.5%

RotoNickel -.15% Monel
89% 7.5% 3.45% 0%

imashooter2
04-06-2011, 11:19 AM
I like to get it for less than 50% of what virgin tin costs. Remember candlesticks are usually weighted (a pewter shell with a base full of plaster).

William Yanda
02-02-2012, 01:35 PM
"Remember candlesticks are usually weighted (a pewter shell with a base full of plaster). "
Sometimes it's not plaster, but yellow stuff-been described elsewhere-that's gooey when it melts.
Gets brittle when it cools-that's the only way I got rid of it.

William Yanda
02-02-2012, 09:06 PM
I hit one of the 3 local Sally Ann's this afternoon. A pewter mug engraved Guiness, 13 oz/$.99, Passed on a creamer that looked like pewter, but wasn't marked as such. Didn't pass the scrape test. Found a cast iron/made in china skillet type affair with 6 depressions. I figure it is a cheap ingot mold for $1.99. The hotplate will make short work of the pewter. Specially since I wrapped a saucepan in a layer of asbestos, then one of scrap sheet aluminum from trimming the house.

letsmeltlead2693
02-04-2012, 12:35 AM
Does it hurt to mix pewter you get from different sources into one melt?

imashooter2
02-04-2012, 01:20 AM
Does it hurt to mix pewter you get from different sources into one melt?

It never hurt me...

letsmeltlead2693
02-04-2012, 01:25 AM
I mean would it mess up the alloy? I have some malaysian pewter that is 97% tin and some cheap goodwill pewter that I melted and wonder if it could melt the two types of pewter together. Would it affect the casting properties? The visual properties?

letsmeltlead2693
02-04-2012, 01:28 AM
I hit one of the 3 local Sally Ann's this afternoon. A pewter mug engraved Guiness, 13 oz/$.99, Passed on a creamer that looked like pewter, but wasn't marked as such. Didn't pass the scrape test. Found a cast iron/made in china skillet type affair with 6 depressions. I figure it is a cheap ingot mold for $1.99. The hotplate will make short work of the pewter. Specially since I wrapped a saucepan in a layer of asbestos, then one of scrap sheet aluminum from trimming the house.

AVOID the use of asbestos. You don't need it for melting lead or pewter. Please throw the asbestos away and if you want to endanger your health with a known carcinogen, please wear a respirator with p100 hepa filter cartridges. If you need fireproof materials try kaowool or fiberglass instead.

imashooter2
02-04-2012, 09:23 AM
I mean would it mess up the alloy? I have some malaysian pewter that is 97% tin and some cheap goodwill pewter that I melted and wonder if it could melt the two types of pewter together. Would it affect the casting properties? The visual properties?

A more homogenous alloy would be an advantage to casting.

2muchstuf
02-04-2012, 10:23 AM
Last week I melted my flea market finds into ingots,
4 glass bottom mugs, a large bowl and a tall tea pot looking thing(maybe for wine).
Made 4.25 lb.
Total investment $6.25

Also passed on 3 fancy bowls that totaled $13 and I'm still kicking my own but
for being cheap.
Probably went 2.5 lb.

2

Iron Mike Golf
02-04-2012, 02:25 PM
I carry a small digital postal scale whe I hit auctions and flea markets. I discount candlesticks for the likelyhood of plaster or resin weighting. I like pitchers, goblets, and sugar/creamer sets.

You see coffee/tea pots with wooden handles and I discount those. Now, the ones with wrapped handles (either rattan or PVC) have pewter under the wraps.

After a year of just keeping my eyes peeled (my wife and I like flea marketing and have been doing it since before I started casting), I have somewhere north of 30 lbs of ingotized pewter.

imashooter2
02-04-2012, 03:31 PM
I like teapots with wooden handles as much as any other pewter... It's all about price per pound. If the price is right, the piece goes with me.

303Guy
02-06-2012, 05:18 AM
Copper in the boolit alloy gives it toughness. 1.6% is the max I think? before it does bad things to the alloy. (Or is that 0.16%? I forget now).

imashooter2
02-06-2012, 08:29 AM
1.6% would precipitate out of the alloy in a big way... It would give you fits with a bottom pour.

EDG
02-07-2012, 10:12 PM
This is interesting reading. I need to get my pewter scrounging skill up to speed.