fluxing with kitty litter?

[1Hawkeye]

I pulled off a major haul of casting equipment at a swap meet today. One item I got was a Lyman mag 20 furnace ( for a whopping 20 bucks) it works fine but it had a couple of handfuls of what looked like kitty litter in it. I dumped out the loose contents of the pot. Which was some of the litter and a bunch of badly cast .45 cal swc's and there was still litter in the solid lead in the bottom of the pot. This came to the surface when the lead melted. Iv'e always fluxed with beeswax and I have heard of folks using sawdust but fluxing with kitty litter is new to me. I will say that the molten lead was very clean and shiny. Is this a new development cause Iv'e been casting over 30 years and never heard of it.
Thanks for your input.

[Dan Cash]

I used litter once but it made ***** bullets. Just kidding. I am not big on any think that remains a solid in the melt,litter, saw dust ect. Bee Wax is excellent but spendy for flux. I use lots of parafin as partly used ornamental candles seem to come my way for free. Another alternative is canola oil or peanut oil. It burns a long time and leaves a crust or coating similar to bee wax.

[Rcmaveric]

The kitty litter prevents the rapid oxidation of the liquid lead and its elemental alloyed components. Same concept as putting in a bunch of wax to create a layer of liquid wax to prevent oxidation. You can do the same thing a layer of sawdust. I personally don't do the kitty litter thing. I do most of my fluxing while smelting the lead. I try to keep the casting pot as clean as possible. Once the lead is in my pot I use just the tiniest bit of flux to keep it all liquid and put the oxidized elements back into the melt. Sometimes a blow torch helps.

[Pipefitter]

Kitty litter by its nature is moisture absorbing. I would be wary of putting anything that holds water in my lead pots, I do not want to have a visit from the Tinsel Fairy.

[Mr_Sheesh]

Kitty Litter is basically clay. Bentonite IIRC. (Unless its a shredded newsprint variety?) I use paraffin but am leery of sawdust and doubt I'd use kitty litter...

[dikman]

Can be Bentonite, ordinary clay, shredded paper, silica crystals (and who knows what else is added). Personally, I wouldn't use it, stick to what you know works well for you.

[jmsj]

I use it all the time. It is the unscented kind without any additives or just regular oil absorbent (same thing, I think).
I only use clean lead that has been smelted, fluxed twice and poured into ingots in my casting pot. The Kitty litter makes a barrier to atmospheric air and stops oxidation same as the others but with out the smoke. When using a 2 cavity mold, I just throw the sprues back into the melt through the litter and they do not splash lead. Using a 6 cavity mold, the sprues start to build up too fast and they start to build up pretty thick. I can take a break from casting and stir them back into the melt using a wooden stick.
As for being hydroscopic, I usually refill my casting pot full when I finish casting. When I get ready to cast it takes a while for the pot to melt all the lead, maybe this gives it enough time for the heat to drive off all of the moisture in the clay. All I know is that I have never had a visit from the tinsel fairy in my casting pot using kitty litter/oil absorbent.
jmsj

[lightman]

I've never used kitty litter because I've always been concerned about any moisture that it might attract. But other casters report that it works. I've always had access to wax (paraffin) and sawdust so alternatives were never needed. I only use sawdust in my smelting pot, never in my bottom pour casting pot.

[D Crockett]

I use kitty litter on top of the pot to stop oxidation but I do not see how you use it as a flux it stays on top of the mix in the pot D Crockett

[Walter Laich]

After reading all these posts I'm getting the feeling you are talking about clean kitty litter

think I've found my problem

;-)

[Echo]

After reading all these posts I'm getting the feeling you are talking about clean kitty litter

think I've found my problem

;-):razz:

[lightman]

:cry:

[bangerjim]

Why bother!!!!!!!! Pine sawdust is everywhere! Litter is moisture absorbing clay (generally bentonite) and will NOT flux or reduce anything at all!!!!!!!!!

Get some pine sawdust and bees wax (candles/crayons/parafin if you are really cheeeeep) and do what all of us have been doing for many generations!!!!!!!! Why deviate from the established norm.

Banger

[Shepherd2]

I've used kitty litter as a barrier to prevent oxidation for years and it does a great job. I leave it in the pot until it starts to break down and get powdery. Then I change it. I've never had a problem with moisture as the gradual heat from melting the alloy dries the litter.

[Char-Gar]

I use kitty litter on top of the pot to stop oxidation but I do not see how you use it as a flux it stays on top of the mix in the pot D Crockett

This is the correct answer. When the melt it up to temp, it is fluxed and the litter it added which floats on top as a barrier to air. The negates the need for continued fluxing. I have done this for many years. I also preheat lead ingots that go in the pot as needed. They go down through the litter and there is no need to reflux. Lots of us old timers have done it this way for a long time.

Again, the litter is not used as a flux.

[Thumbcocker]

Been using clay based cat litter on top of the pot for years. Lets sprues and reject boolits in but keeps air out.

[BD]

IMHO Char-gar and Shepard2 have it right. If you use ingots that have been well fluxed and stirred when they were made, a layer of bentonite cat litter on the top of the mix in your pot negates all most all of the oxidation that occurs during a pour. It also allows you to "float in" ingots warmed on the rim of the pot without any further fluxing so you can go through a 100 lb or so in a master caster without interruption. I just stack the ingots on top of each other as I add them, pre-warmed from the rim of the pot, and let them settle down through the cat litter as they melt, stopping to stir only very occasionally. This keeps the alloy clean and at a pretty constant temp. At the end of a session I'll stir the pot well and any gas checks or other **** that snuck in there comes up into the bentonite where you can easily scoop it off without carrying away any of the alloy below.

[Mark Daiute]

BD- Moosehead Lake? As in Greenville, as in Maine, as in 45deg. North?

[copdills]

I just don't think so:-|

[1Hawkeye]

I get it now. Its a anti-Oxidizer so to speak that prevents air from corroding the lead underneath it. I also noted it acted like a heat barrier that pot went from cold & solid to ready to pour in record time. I think I just adopted a new technique at least for that pot. I might put some in my drip o matic too but that will be for the neighborhood cats now that I have a good furnace.
Thanks All

[EDG]

You could float almost anything inert on top of lead to act as a barrier to oxygen.
That could be a stainless plate, steel shot, or glass marbles.

One of the largest medical products foundries uses argon gas to do the same thing with their ASTM F75 cobalt chrome alloy. They have an argon drip line that provides a very small supply of argon to the top of the crucible. The alloy is melted and stirred by the current in induction coils. The argon provides a blanket of inert gas on top of the melt pretty much in the same fashion as the gas supply in a GTAW torch.

The next step up in shielding alloys is used with casting titanium.
Molten titanium is highly reactive it is melted in a vacuum furnace. To be sure the atmosphere is free of oxygen the pressure vessel is evacuated and purged with argon before pumping the chamber down to a partial pressure. Any residual gas is going to be a tiny bit of argon. The surface of titanium castings still have contaminants from the investment casting shell so the titanium has the alpha case removed by chem milling.
The titanium castings are also HIPPED which is hot isostatic processing. The castings are heated in a vacuum furnace to near the slumping temp in the presence of about 30,000 PSI argon pressure. The plastic like metal crushes any gas porosity and makes the gas diffuse back into the metal. This "heals" internal porosity defects and improves the fatigue life of castings like knee components that are load cycled all day long for years.
After hipping castings are xrayed and liquid penetrant tested. The xrays look for cracks and other internal flaws. The liquid penetrant looks for porosity that was connected to the surface of the part. HIPPING cannot heal a surface connected porosity defect since the porosity will have the same gas pressure internally and externally.
Maybe in a few decades younger guys will have better techniques to protect their alloy than those used by cats.

[dikman]

Personally, I reckon we're overthinking this whole process. A Promelt holds about 22 lbs. or so, when you're casting it needs topping up fairly regularly, so it's not as if it's sitting there for hours slowly oxidising. When I top mine up (with clean ingots/sprues) once it's melted I throw a small piece of wax on, stir it around, scoop off the gunk and start casting. Had no problems so far. The gunk, which will have some lead in it, gets thrown into the melting pot next time I melt down a batch of range scrap so any lead doesn't get wasted.

What we're doing hardly needs to be "laboratory clean".

[tankgunner59]

I use sawdust to flux my smelter, but I use paraffin for my furnace. Each works very well so I go by the old motto, if it ain't broke don't fix it.

[Dave W.]

I have used wax, saw dust, even some old dry grass on occasion. They all seemed to work fine. Never tried to use gunpowder, that just doesn't seem the best to use.:razz:

[Kraschenbirn]

+1 on what Char-Gar and Thumbcocker said. Been doing it for years without any issues. Keeps the pot clean (no pun intended) and absorbs/retains any crud that might float to the top of the melt.

Bill

[EDG]

Over thinking? Not a chance if you look at the cruddy bullets cast by most casters. Any convenient way to keep the metal clean is better than bullets loaded with inclusions and dross. Commercial methods are good because commercial companies have developed them as part if their competition for business and existence in the market place.

[Littleton Shot Maker]

long ago- told to me by a guy that had been casting and making shot for 30+ years..that was 10 years ago-
he uses the cat litter on top of his dutch oven smelter-to be the filter-
the lead goes down into the mix and the crud stays on top. clips, jackets, rocks etc etc…
he still fluxed- with parafin/beeswax mix to get the tin/lead/Ant to bond- the litter was the 'poor mans charcoal filter' for lead - the way he told it to me…
but he told me also - most folk get into a rush and over heat the lead- so he always did his smelting at just around 600f not much more….lower if he could get the alloy to melt down through the litter...

[captaint]

I used kitty litter for about a year. I felt like I had dirty boolits constantly, so I switched back to just the wax. I'm much happier now. It's much easier to keep my melt clean..

[greenjoytj]

I read about using saw dust as flux, so I tried our cat litter material. We buy the type made from ground corn cob as it is advertised as toilet flushable. It work great put smokes heavily till it chars.

[Smoke4320]

Tryed kitty litter once.. Wife got really mad when she could not find her cat.. Guess i should have removed it first

[trapper9260]

I use ground corn cobs.The same one that i use on my brass. But the unused one.It works for all I do with it.I had a farmer ground up some cobs for me years ago in his feed mill for me. I have alot to last me some time.Some times when I am smelting ,I use wood for my heat and it is low heat at first before the ashed a build up.I take the ashes and put in in the pot to flex also.Beside use the corn cobs.Since it all that is added for flux turn to ash. My alloy is clean after and put in igot after. I also flux when casting with the corn cobs.

[wjham77]

I recently tried kitty litter (Walmart special kitty natural clay) in my Lee 4 20 and I like it, I still flux with wax. I've also had issues with dirty bullets recently, I really hope it's not the litter, cause it really helps cut down on the need for fluxing. I cleaned my pot and am gonna start with different batch of lead. First without the kitty litter, then once I know I getting good bullets, I'm gonna try the litter again, and see if it makes a difference.

[Mr_Sheesh]

Clay type cat litter (Bentonite) wouldn't likely do, but the paper or cob ones would.

[gwpercle]

I have access to pencil sharpener shavings , a pinch of shavings in my casting pot with a pea sized ball of bees wax thrown on top works great . Stirred with a wooden paddle and skim off any dross. The cedar smells good too.
I never did care for the layer of clay kitty litter floating on top...just seemed to dirty up things.
Gary

[john.k]

You get a strange effect with lead where contaminants stick to the sides of the pot,even tho they are much lighter than lead.Then come to the surface when disturbed,resulting in dross on the lead surface,that will end up in a ladle cast.This is the same stuff that causes problems with pour valves.Its often fine sand.