Argh! Wasted pewter.

[TexasGrunt]

I've been scoring a bit of pewter on an auction site. Today was time to start smelting. Everything was going well till I had a piece of Bolivian pewter. Instant mush. My melt temp was right at 700°, Lee pot but checked with my Lyman thermometer, I'm not sure if that big bowl had silver in it or if it was zinc. I've got close to 10 lbs of contaminated pewter.

188928

Ya can see how mushy it was. That was the stuff dripping out of the pot. I did notice that there was a lot of liquid metal seeping out of the mush. I would hope that that metal was tin.

Has anyone else ever ran into this problem? Any ideas? Any solutions?

[308Jeff]

Dang. That IS a mess. Sorry, brother.

I don't have any answers, but I'm subscribing to find out what someone else has to say.

[runfiverun]

zinc will mix with Tin no problem.
tin loves the stuff, they use zinc to strip tin from lead alloys at the foundry's.

I think you got what they call white metal, it's used to make costume jewelry and stuff like that.

you really need to be melting your pewter down at more like 450-f.

[jsizemore]

Keeping your melt temp around 450-475°F is the proof that what your melting is tin based.

Weighted Leonard/Bolivian candle sticks are good pewter. I've never seen a Bolivian bowl.

Looks like you have a nice reminder of what not to do in the future. Most folks have no idea what is real pewter.

[TexasGrunt]

Without a PID there's no way to get my Lee to run that cool.

[rancher1913]

I use my smelting set up and keep the temp just kind of liquid, then add unsure of pieces a little at a time, if it don't melt quick it gets pitched in the junk pile

[Bzcraig]

Without a PID there's no way to get my Lee to run that cool.

I don't have a Lyman thermometer so this may be partially redundant, but get a BBQ thermometer with a 6" probe on it, stick it in your Lee pot and adjust your settings as needed. I did that for years before getting a PID to watch my casting temperature.

[BK7saum]

I don't have a Lyman thermometer so this may be partially redundant, but get a BBQ thermometer with a 6" probe on it, stick it in your Lee pot and adjust your settings as needed. I did that for years before getting a PID to watch my casting temperature.

I think he is saying that his rheostat switch doesn't let the pot run at that low a temp. The PID cycles the power on and off to maintain the temperature setting.

[jsizemore]

Now he has the motivation to PID it. Most of the inexpensive thermometers we use lose some of their sensitivity and range with use.

[TexasGrunt]

Weighing the cost of a PID for the Lee, which I only use to melt pewter, to the price of pewter, I can't see a break even point.

The pewter in question melted at about 550° but was extremely slushy. I turned the pot up to see if I could get it to flow.

The temp was 700° when I took that picture. I could spoon large piles of the slush out of the pot.

[Dusty Bannister]

In "Cast Bullets" by E H Harrison, he describes how they would deal with contaminated alloy. Fill the pot half full of good metal, and bring it up to casting temp. Add one ingot (one pound) of the contaminated alloy bring it up to temp, and trial cast. If it casts normally, add one more ingot. Bring it up to temp and trial cast. When casting becomes a problem, fill the pot with good metal and use the alloy for non demanding purposes.

In your case, you might try to ladle cast this contaminated metal into a long thin ingot that you can cut into smaller pieces. Then try adding 1% to a good metal and trial cast. It might be that the contaminated alloy will be diluted sufficiently that the tin will be beneficial and the zinc will not be a problem in your alloy. If that fails, make and sell trot line weights.


http://castboolits.gunloads.com/showthread.php?294210-What-does-zinc-do-that-makes-it-so-bad

Read post #10 for a better explanation of what zinc might do in your alloy.

[Chill Wills]

http://castboolits.gunloads.com/images/misc/quote_icon.png Originally Posted by Bzcraig http://castboolits.gunloads.com/images/buttons/viewpost-right.png (http://castboolits.gunloads.com/showthread.php?p=3963722#post3963722)
I don't have a Lyman thermometer so this may be partially redundant, but get a BBQ thermometer with a 6" probe on it, stick it in your Lee pot and adjust your settings as needed. I did that for years before getting a PID to watch my casting temperature.



I think he is saying that his rheostat switch doesn't let the pot run at that low a temp. The PID cycles the power on and off to maintain the temperature setting.


The Lee pot does not have a rheostat. It does however have a simple bi-metal switch to control the setting.
To adjust;
You open up the box behind the pot and adjust the heat range by SLIGHTLY bending the leg closed.
Don't over do it.
In your case you want the control knob to have some more lower range control because your pot is running more in the hot range. By closing the leg you will have more midrange control. It is a bit of trial and error but not hard to get right.

[runfiverun]

I'd just un plug it and plug it back in.
or wire a switch inline with one of the wires.
click, click cost like 3-4$ [that's American money]

[TexasGrunt]

I was able to recover a lot of the tin. I put the metal in a pan on my hot plate. Got it to 450° and carefully poured out the liquid metal.

[308Jeff]

I was able to recover a lot of the tin. I put the metal in a pan on my hot plate. Got it to 450° and carefully poured out the liquid metal.

Nice.

[imashooter2]

Sorry to say I've seen it. I'd handled a whole lot of pewter by the time this happened to me.

http://castboolits.gunloads.com/showthread.php?127929-Pewter-pictures-and-hallmarks&p=2863730&viewfull=1#post2863730

[MaryB]

You can put together your own PID for under $50...PID with type K thermocouple https://www.amazon.com/dp/B00BVWYI8G/ref=biss_dp_t_asn they also have the package deal with the solid state relay. Add an electrical box and good to go. I have built several lower temp ones for fridge controllers.

[jsizemore]

I use the same PID controller with my 5 lead pots. Output from the relay feeds power to a standard outlet on the back of the controller box. I run each pots thermostat at max and let the PID control temp. I bent a heavy coat hanger into a stand and have an alligator clip on the end to use as an adjustment for different pot heights. I've got about $40 sunk into my setup. I've got about $30 in a PID to control the temp for my lubesizers. Once they're set you ain't got to worry about them.

[TexasGrunt]

Sorry to say I've seen it. I'd handled a whole lot of pewter by the time this happened to me.

http://castboolits.gunloads.com/showthread.php?127929-Pewter-pictures-and-hallmarks&p=2863730&viewfull=1#post2863730

Yep. I cut just like pewter, felt like pewter.