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tomf52
01-01-2006, 12:06 PM
There has been much talk on the board here about the various methods and types of materials for fluxing our lead pots and in reading them a question has arisen in my mind. It seems that many of you claim to flux very little while casting. I can only assume that those of you who make this claim are using bottom pour pots. Am I correct assuming this? I cast with a ladle and if I don't flux fairly frequently, I get a considerable buildup of junk on the surface which seems to find it's way into the molds if I don't keep the lead clean. Can somebody enlighten me if I am incorrect in my assumptions and tecniques. Thank you for any help you can give.

1Shirt
01-01-2006, 12:11 PM
I bottom pour, and only flux befor I start, and when I add lead. When I used to dip, I had similar problems as you, and had to flux more often. Hope this helps. Happy New Year.
1Shirt

Oldfeller
01-01-2006, 01:15 PM
Well, we either don't flux at all or we flux continuously, take your pick.

Flux contains carbon atoms that can be broken free by the pot heat to join in with the oxides in the metal (snatching the oxygen atom from lead oxygen bond) freeing the pure lead metal and making a resulting much lighter carbon oxide which then floats to the top of the melt.

Here are some of the ways we as a group have done it.

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Stir your melt with a small wooden stick occasionally (hey, that's like work , isn't it ??).

Put sawdust on top of your melt and let it smoke all the time and stink and catch on fire occasionally. Use cedar sawdust if you want any form of redeeming smell to the affair.

Put oily sawdust ..... (ugh)

Buy a small bag of cheap clay-based kitty litter (read the bag, most is clay based, dolomite, etc). Sprinkle a 1/8 to 1/4 inch layer on top of your melt. Add your sprues and ingot to the pot by depositing them on top of the kitty litter. As they melt, they trickle down through the litter getting fluxed all the way. The entire top of the melt is in continuous contact with an entire layer of flux and it is sheilded from further air oxygen contamination to boot.

Kitty litter works best, it doesn't stink or smoke and it shields your pot from droplets of moisture and from air (oxides again) and from the excessive heat loss from the top of the melt pool that makes your pot have to run all the time.

It is possible using a small LEE bottom pour pot to keep up with a 30 caliber six banger mold running at full steam by pre-heating your ingots on the pot edge and intentionally keeping the pot pretty much full all the time by adding pre-heated ingot to the top of the kitty litter.

(you don't have to wait until it melts, just keep the mold going while it melts)

And if you really feel like you have to, you CAN take a long steel tea spoon and stir your metal periodically right throught the layer of kitty litter. It doesn't really do anything that adding an ingot or a sprue wouldn't do anyway, but it helps "fluxers" get over their stir addictions and habits by weaning them off a little bit at a time.

Just pour the litter off the top of a cold solidified melt mass and add a fresh layer every time you crank the pot up. If you wait too many sessions between changing and the litter gets really contaminated with oxides, you will need to scoop it off the top with the teaspoon when the pool is molten. That will serve to remind you to keep it replaced and fresh. It's not like the entire bag of litter didn't cost like what $3 ???

Bent Ramrod
01-01-2006, 09:04 PM
Tomf52,

I cast with a ladle and generally a single-cavity mold. Used to use a Lee 10-lb pot and then got their 20-lb pot when that finally burned out. I flux once when the metal is melted (to get any dirt and crud out of the metal), and afterwards only when the metallic dross on the surface gets unmanageable. Generally once in the course of casting one charge of the 10-lb pot; maybe 3 times with the 20-lb.

Generally wheel weights and linotype melt low enough so I can corner a small pool of clean metal surface against the side of the pot and sweep the dross away from that area of the metal for a pretty long time. I tilt the ladle and fill from this clear area. The closer the alloy is to pure lead, the higher the temperature and the more the dross is that dark purple-to-yellow grunge which is hard to sweep back with the ladle. Then I have to flux more often. The buildup of dross on the ladle spout is also a factor on fluxing, but often I just touch a wax candle on this part, and run a wax-coated wire on the inside, let it smoke out and keep casting.

I try to keep two molds hot when I'm casting (it was hard to do this trick with the 10-lb but it's easy with the 20-lb) and any flux time means the molds are cooling off. Unless they're not filling out or there is visible dross in the cavities, I don't flux except when the conditions above show up.

buck1
01-01-2006, 09:20 PM
LOTS of opinions on fluxing!! Some swear on doing it often , wile others dont flux at all.
I flux when I see a noticeable amount of dry film on the pot. With a ladle, or a hotter than normal pot I flux more. I flux very often as tests I have ran show the wt changes. Others have ran the same tests with differnt results.
I do belive in fluxing ALL the gray back in to the melt. Lots of mixing to get that done.
Just my $.02 ....Buck

Lloyd Smale
01-01-2006, 09:41 PM
I flux once a session at the beginning and thats it other then fluxing when smelting wws.

Junior1942
01-01-2006, 10:15 PM
I haven't fluxed in years. I read several articles which said it was a useless step, so I tried casting without fluxing to see what would happen. Nothing happened. So I quit fluxing.

JohnH
01-01-2006, 11:58 PM
There has been much talk on the board here about the various methods and types of materials for fluxing our lead pots and in reading them a question has arisen in my mind. It seems that many of you claim to flux very little while casting. I can only assume that those of you who make this claim are using bottom pour pots. Am I correct assuming this? I cast with a ladle and if I don't flux fairly frequently, I get a considerable buildup of junk on the surface which seems to find it's way into the molds if I don't keep the lead clean. Can somebody enlighten me if I am incorrect in my assumptions and tecniques. Thank you for any help you can give.

Get yourself a bottom pouring Rowell Ladle www.theantimonyman.com The ladle has a "spout" that reaches to the bottom of the ladle so you alwasy pour clean metal. When you dip in to fill it, clear away a clean spot and dip the edge in and fill it.

The oxidized metal on the surface is a result of the oxygen combining with the surface layer of the melt. Everytime you expose fresh metal to the atmosphere new oxidation takes place. Covering the melt with kity litter will help stop this and you can rake it aside to dip the Rowell and rake it back. Rowells come in 1 pounders and up A filled ladle will make quite a few pours and cut the times you have to dip into the put, cutting the oxidized metal on the surface that makes you want to flux, unless of course you like fluxing