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KennethF
11-20-2008, 10:17 PM
I have gathered some scrap metals to smelt and cast to ingots. What should I flux my molten metal with to clean and mix the alloys before if pour into the ingot molds? I know that waxes can be used and I have read here that saw dust works well. Thanks for your ideas.

docone31
11-20-2008, 10:29 PM
I use Kitty Litter. I also, from time to time use a dab of liquid solder flux. Most times I do not need to flux, I just stir and toss the dross.

oneokie
11-20-2008, 10:30 PM
Anything with lots of carbon in it. ATF fluid, used motor oil. Light the smoke to burn it off. Do this outside, and stay out of the smoke.

timkelley
11-20-2008, 10:33 PM
Try the sawdust and stir really well with a stick, I save cutoffs and sawdust from my woodshop.

xr650
11-20-2008, 10:33 PM
I use Marvelux for the time being. I'm not a big fan, but I have it and will not throw it away.
I stir with an old mop handle and a ladle.
When the Marvelux is gone I will be using PMWFCFF or my imitaition there of.

Welcome to the forum and the addiction.

KennethF
11-20-2008, 11:04 PM
Thanks for the imput everyone, sounds like many things can be used. I have ordered CFF and it should be here any day now. In the past I have used waxes. I have not cast ingots or boolits for many years now but am about to begin again. Now that I have retired and have more time to do what I like to do.


KennethF

pps
11-20-2008, 11:38 PM
I use sawdust/shredded ivory soap stuck to a slotted wooden spoon with some lard and just stir the concoction into the alloy.

John Boy
11-20-2008, 11:41 PM
Plus 3 ... for sawdust. Stir with a split off piece of a wooden paint stirrer

Meatco1
11-21-2008, 02:05 AM
Just plain sawdust does a terrific job.

compass will
11-21-2008, 07:24 AM
I use borax. the kind you would use to add to your wash.

I heard about it here. Just spinkle a couple pinches onto the top. No smoke. mix it up and it all starts to clump together. Scoop it off and you got clean lead.

It's so clean I can even do it on the electric pot in the garage while casting without driving myself out of the garage.

HABCAN
11-21-2008, 07:41 AM
Finely grated Ivory Soap works wonders, even indoors. Sawdust is good, but smokes. Paraffin wax works great, but smokes badly. Your pick.

jdgabbard
11-21-2008, 10:30 AM
Ivory works wonders. But it is REALLY messy in the pot. You'll spend some time skimming all the crud off the top. Beeswax works pretty nice, and you could use boolit lube in a pinch.

ryan richards
11-21-2008, 10:46 AM
HI guys,

It appears that sawdust is a favorite choice for fluxing.

As a new guy just starting, the obvious to the experienced fluxer is a mystery to a new guy who knows nothing.

Some simple questions assuming that you are smelting / casting w-w.

1) How much sawdust do you use? A teaspoon?, a tablespoon, a handfull?

2) How often is it done?

3) Is it sprinkled over the surface or dropped in as a lump?

4) Is the fluxing process different if you are smelting or casting?

primersp
11-21-2008, 11:11 AM
HELLO
i have use for many years parafine or beewax but a day i see on a article that pine resin works good i try and really it's worked great and smelt good i never try borax because it's hard to find here.
regards

Linstrum
11-21-2008, 11:29 AM
From a chemical standpoint, pine pitch/rosin is the best for preparing boolit alloys. I wouldn't buy it, it costs way too much, but if you are near some pine trees, go collect the clumps of pitch that drip and collect under the trees on the ground. I have picked up five pounds of pitch from under just one tree, so it is not hard to get.

If you don't have a free source of pitch, just use what the other guys here have already mentioned. I have quite successfully used sugar, sawdust, charcoal, plastic sandwich baggies and pieces of plastic shopping bags, straight 30w non-detergent motor oil, lard, cooking oil, paraffin wax, and beeswax, just to name some.

Don't use borax to clean your casting alloys, it very effectively removes the tin and antimony from the alloy instead of returning them back into the melt. That is how it works and why it is used in metallurgy, it forms metallic borate compounds with metal oxides, which then melt at a very low temperature and float on top of the molten alloy. The purpose of using saw dust and such is to chemically reduce the oxidized alloy constituents and turn them back into metalic form, not get rid of them. The correct term for this is "reduce", not "flux".

Fluxing means to remove oxidized metals by chemically converting them into a benign and more-easily removed form, and we are definitely not doing that when we prepare old wheel weights for casting. We are instead reclaiming alloying constituents and returning them back into the melt, not removing them. Powdered borax WILL protect the surface of the melt from oxidizing, but at the expense of losing valuable alloying constituents. Cat litter also protects the surface from oxidizing and it does not take out any alloying constituents.

How much to use? The main thing is to do it outside and be careful about how much you use, too much lard, oil, or pitch will result in a really big fire, one guy here burned his house down while preparing to do some casting. In a five pound melter I use maybe a 1/4 teaspoon OR LESS of wax, about the same amount of sawdust or sugar. Set it on fire and carefully stir the melt. If you can't get close enough to stir it with it burning, you put in too much. Start small and add a bit more if needed - don't rush it! It doesn't take much, but the more dross present, the more sawdust or whatever you choose will be needed to get a good clean, shiny melt. The same stuff is used for both melting down raw wheel weights and during casting, although I rarely use anything during a casting session since I start out with clean alloy. If the melt needs cleaning a bit while casting, I drop in a pinch of sugar or a pea-sized lump of beeswax or pitch and set it on fire while stirring, then when it goes out I skim off the little bit of gray dross left and dump it in a soup can to cool.

rl482

primersp
11-21-2008, 11:47 AM
like you linstrum i live near pine and i collect the resin directly on the tree a incision
with a large wood cisel and in 2 days a jug is full

Castnshoot
11-21-2008, 02:46 PM
Right now I have a gallon bucket of lard, anything specific I should be aware of?

ryan richards
11-21-2008, 03:48 PM
Hi guys,

I thank "Linstrum" and other knowledgeable members like him who have provided me with the technical information and experience, which can't be found in any other forum, to further my enjoyment of this great activity.

compass will
11-21-2008, 03:58 PM
Don't use borax to clean your casting alloys, it very effectively removes the tin and antimony from the alloy instead of returning them back into the melt.
rl482

Wish this came up in that thread 2 months ago :lol: I just used it on 300 lbs of lead.

Linstrum
11-21-2008, 09:22 PM
Hey, there, compass will, I wouldn't lose any sleep over it, the main thing is you got 300 pounds of lead cleaned up! :p

If your 300 pounds of metal makes good boolits you're doing fine. Lots of us "tune-up" small batches of boolit metal by adding in a bit of solder for the tin content, linotype for the antimony as well as tin, and even exotic stuff like phos-copper brazing alloy for the phosphorus. Depends on what you are shooting it in, too, you probably already know that for some low velocity applications and/or guns with a slow rate of rifling twist, like for .38 Special and .45 ACP, boolits don't always need to be real hard to do a good job.

One thing that gets discussed a lot is having different kinds of powders on hand for various pistol, rifle, and shotgun applications, but I haven't heard as much discussion about having different kinds of boolit alloys on hand for various applications. It does get discussed a lot but not quite on par with powders. I shoot mainly wheel weight alloy but I do have a whole bunch of other alloys on hand, too. I never really intended to do that, though, over the years of scrounging lead I ended up by default with all sorts of alloys that range in hardness from pure lead all the way to linotype, babbit, and pewter.


rl483

38 Super Auto
11-21-2008, 10:13 PM
I think someone posted here a few months ago about using stearic acid. I got some of e[vil]-bay and a little dab will do ya. I have used marvelux, pine resin, sawdust, and paraffin. Paraffin is cheap, but stearic acis really cleans up my melt.

Here's a reference.

http://www.answers.com/topic/stearic-acid


Just my 2 grains worth...

Linstrum
11-22-2008, 02:08 AM
Stearic acid works great - another one of the many materials that gives excellent results. Stearic acid is one of the components found in plant and animal oils and fats, it is chemically combined with glycerin to make glyceryl stearate, one of the fatty esters found in lard and tallow. One advantage of stearic acid is its low odor when burning and is why it is so popular with candle makers. Another one that works for preparing boolit alloy is palmitic acid, also found in vegetable oils as glyceryl palmitate; especially palm oil, from which it gets its name.

Lard works, too, the main thing with it is that it doesn't burn as clean as stearic acid. One of the combustion products of lard and other fatty esters like vegetable oil is a real irritating aldehyde called acreolin that forms from the incomplete combustion of glycerin. Like other aldehydes, it is toxic, but no worse than wood smoke. Shouldn't be breathing smoke from preparing lead boolit alloy, anyway.

Stearic and palmitic acids when reacted with lye make ordinary soap like Ivory, and is why soap also works to prepare lead alloys. When palmitic acid is reacted with an aluminum salt it makes aluminum palmitate soap, which was the first agent used to gel gasoline for making Napalm, and with wood alcohol to also gel it, it makes the original Sterno canned heat that was used for heating the WW2-era GI ground pounder's C-rations or his shaving water in his helmet when a Jeep wasn't handy to heat water in the radiator.

Stearic acid and palmitic acid are also good components for boolit lubes but I don't know what happened to the recipes for using them, might be over at:

http://castboolits.gunloads.com/showthread.php?t=29683


Have fun!


rl484

Whitespider
11-22-2008, 07:24 PM
I use grated Ivory soap, after it melts I sprinkle in some sawdust (wood chips or flakes from a chain saw) and start stirring. Ivory soap alone makes kind of a greasy slime on the pot sides and spoon, adding the sawdust eliminates that problem. Sawdust alone can leave quite a bit of carbon on the side and bottom of the pot, but using it with the Ivory seems to keep the carbon on top of the melt where I can skim it off.

When I "smelting" WW's I'll toss in healthy amounts of both, probably more than is needed but I wanna make sure I'm getting the metal clean and homogeneous before I start pouring ingots.

ddeaton
11-23-2008, 10:47 AM
I am a little slow and maybe didnt read all posts to the letter.

When you add flux, lets say beeswax, you set it on fire? Actually with a lighter?

How do you know when you need to add more flux as you are casting? What are we looking for in the lead pot? Or do we just for the heck of it flux at a given timeframe?

Thanks in advance

OeldeWolf
11-23-2008, 11:30 AM
As I was melting down some range lead, and "fluxing" it, I had a few pots that felt almost silky when I ladled them. That is the only way I can think of to describe how they felt. Is that what they should all feel like by the time they are ready to pour into ingots?

And I will have to try the sawdust with ivory trick, the ivory was so messy I was thinking I was doing something wrong.

blackthorn
11-23-2008, 12:01 PM
All you really need to do is to stir your melt well with a VERY DRY piece of 1x2 board or even a VERY DRY 1&1/2 to 2 inch tree branch (pine works well). Scrape the sides and bottom of your pot well to loosen any crud that may be stuck to the pot and you are good to go!

DoubleBarrel
11-24-2008, 04:00 PM
Hello Everyone, I'm new to this forum and would like to know if anyone has tried using liquid soldering flux such as "stay clean" made by Harris? It contains zinc chloride. Thanx,DB

Linstrum
11-25-2008, 04:51 PM
Hi, DoubleBarrel, welcome to the forum.

Zinc chloride and ammonium chloride soldering fluxes work great for soldering applications but preparing boolit alloys for casting does not involve the type of chemical action that these commercial soldering fluxes perform. Besides that, those types of fluxes rapidly attack and damage steel and brass moulds.

The action required to clean up casting alloys is conserving alloy constituents, not chemically dissolving them for removal, which is what soldering fluxes do. I hope this helps a bit.

DoubleBarrel
11-25-2008, 05:21 PM
Thanks Linstrum, I just happened to find a small bottle in my plumbing box and wondered if it would work. While I was digging around , I also found a large chunk of lead that was once used to contain radioactive isotopes.This thing must weigh 30#. I was going to cut it up and turn it into ingots, however it's snowing like mad here and deer season just started!