Smelting WWs - forgot to flux

[CTI1USNRET]

Yesterday I melted down about 40 lb of wheel weights and made ingots. I didn't flux. I just stirred and skimmed the crud off the the top with a stainless steel slotted spoon. I used a propane burner and a 20 lb capacity cast iron pot. It was windy out and I had a tough time maintaining temp. Because of that, I don't think it got anywhere near the melting point of zinc. The thermometer never got past 600.

Will zinc weights float? If the zinc did melt, will resmelting at a lower, controlled temp cause the zinc to separate out and become skimmable?

Is fluxing absolutely necessary? And should I flux when I cast from my bottom-pour?

[N4AUD]

When I smelt the zinc weights that I miss float to the top, as do any steel weights.

[groovy mike]

zinc floats, but it would be VERY unusual fro you to have 40 pounds of wheel weights with NO zinc or iron weights in there....

[rondog]

I've only smelted once, the same way you did. Except I was out of the wind. I found it tough to get the melt hot enough to liquify good, and the zinc weights floated up long before the lead got good and watery. I scraped off an unholy amount of garbage! Made my ingot "biscuits" in muffin tins.

But I didn't flux either, I wasn't intending for my ingots to be used right away, I was basically just converting them from ww's to a more manageable and easier to store form. I'll smelt them again before recasting them as new ingots.

I recently got a bunch of used casting stuff, including a LOT of ww ingots and a Lyman 4-bar ingot mold. I found that those little bars fit perfectly in .30 cal ammo cans for easy storage and transport! So, when I re-smelt my biscuits, I'll re-pour them into the Lyman molds and make more bars. I have lots of empty ammo cans.

[JWFilips]

I have only been casting since January of this year So I'm not that experienced as the others here but I can give you this piece of advice ( I learned it the hard way)
Smelt everything until it is very clean & that means using lots of sawdust and spending time playing the melt through the sawdust sitting on top Scoup off the crud until the metal is shiny then Flux again with saw dust and repeat the mixing as above Scoup all the dross & charred wood dust off again maybe add a small piece of beeswax ..mix in well and then lade off your clean ingots.
I do this also to mix up my different boolet alloys These too I make in the smelting pot That way I know they are very clean before going in my casting pot. I think "Duke In Maine" had one of the best cleaning & smelting articles ever posted here I'm not sure where it is Maybe someone could find it an post the link

[Jon]

Fluxing isn't really necessary for making ingots, although it does help. Just flux the ingot lead well before you start to pour out into molds.

[bangerjim]

I flux/reduce 3 times on EVERY smelting melt. I make sure all my ingots are 110% pure so I do not have to mess around with fluxing in the casting pot to get crapola out that should have been eliminated in the 1st place......in the casting pot - only beeswax to reduce the tin back into the CLEAN lead!

You could remelt your ingots and do it right using wood shavings and paraffin. I would. But that is just me. That way you will know you do not have any "bastard" dirty ingots in your stores.

bangerjim

[JWFilips]

Right with you bangerjim.
I was checking the forum for that Article and see there is no more "DukeInMaine" guess he is "DukeInFlorida" now?

Anyway here is his quoted article that I had saved to my computer (Hope he doesn't mind me re-posting it & I'm not sure if this will be a problem so Mods please let me know if so)



Here goes..... I am VERY fussy with my ingots. From the sounds of it, I would NOT WANT some of the ingots that some of you produce. Not clean enough for my guns.

Here's the basis for how I do it: I want as close to PURE alloy as I can get. NO GRIT remaining. NONE. Every bit of grit that you allow to enter an ingot becomes abrasive that wears out your barrel. At a commercial lead processing plant, they use very expensive ceramic filters that get all grit out. We hobby smelters can't afford the expensive ceramic filters, so we have to FLUX like crazy to get the lead as clean as possible.

So, here's my system:

1) I always leave the last inch of molten lead in the pot from the previous smelt. I allow that to cool, and mark what it is, with a Sharpie. Next time I smelt that alloy, I put that disk back in the pot, which maintains 100% contact with the smelting pot, and therefore melts fast, giving me a good lead puddle for the boolits/range lead to melt into. If you skip that step, the edges of the range lead have little contact with the smelting pot, and will take longer to start melting.

2) I add a couple of inches of range lead into the pot, and allow that to come up to temperature and melt. I DO NOT fill up the smelting pot........ To do so would introduce too much copper jackets and other debris that needs to get skimmed off. I do my adding in layers, and that goes very fast. Add/Skim/Add/Skim, etc. Continue adding and skimming the big stuff off the top until you have a pot pretty full. The previous comment about the strength of the stand is worth paying attention to. One summer day a couple of year ago, I was smelting 200 pound batches and was horrified when I noticed that the stand leg had started to sink into the hot top, and the stand was dangerously leaning. I had to be very careful to not knock it over while fluxing. Once you have a safe pot full of molten lead, with only the BIG STUFF skimmed off, it's time to start fluxing.

3) The fluxing is the process or technique for separating the grit and other small debris from the metal. You want to end up with as clean a metal as you can, for the sake of the longer life of your guns. The lead is not only heavy, but very dense. The larger stuff that you skimmed off had enough flotation ability to float itself to the surface. The smaller grit does NOT have enough flotation to push itself easily through the dense metal. That's what the fluxing techniques does........ it opens pathways through the dense metal for the small grit to make it's way to the surface.

4) Stirring and the addition of fluxing agents assists with making pathways. It also, and this is an important aspect of fluxing........... it also provides "bonding agents" for the small grit particles to stick and adhere to, clumping them into bigger pieces, for easier removal. So, stirring with anything, a metal spoon, a wooden stick.... when done correctly, will open eddy currents (think whirlpool action) that will allow the grit to make it's way to the top for skimming. And, agents like sappy pine, motor oil, pine sticks (dual purpose), old candle wax, parrafin wax, etc act as perfect fluxing agents for the other part of the fluxing action. Pine saw dust is just about one of the best fluxing agents you could use. It's sappy enough to provide the sap agent that allows the grit to stick to it. And, the small particle size assists with creating nice pathways to the surface, when stirred into whirlpools through the lead. Hard wood saw dust isn't as good, but better than nothing. Get bales of pine sawdust at your local feed and grain store. They use it as horse bedding. You could also use pine shavings, but it's not quite as good as pine sawdust.

5) I grab a handful of pine sawdust, and toss it onto the surface of the molten lead. I use a stainless steel slotted spoon with a long handle (bbq type spoon) and start stirring right away. I stir right to the bottom of the pot, pulling up all the grit I can from the bottom. Keep stirring.... The sawdust will eventually become charcoal, and will soon burn into ash. You want to skim the charcoal and all the grey powder grit that floats to the top off the lead with the edge of your spoon, before it turns to ash. Go slow with moving the edge of the spoon through the lead, and you will see that it's easy to pick up the skimmed material. Pull it slowly towards the edge of the pot, and turn your wrist, and you'll see the grit (grey powder) in the spoon. When you are done with the initial sawdust flux, the top surface of the lead should be somewhat shiny. However, the lower portions of the lead are still nasty! I do this sawdust flux about 4-5 times, or until I start to see dramatic reductions in the amount of grit I am picking off the surface. For some really sandy range lead, I have been known to flux with the pine sawdust as many as 10 times before moving to the next step. Be as fussy as you want to be. It's your lead! And, your guns!

6) Once I have achieved some level of cleanness with the pine saw dust fluxing, I switch over to paraffin wax, which is finer agent, and will get more of the smaller particles out. Old candles are always plentiful. Yard sales are a great place to get them for almost free. I cut them into peanut sized pieces, and toss a piece onto the top of the molten lead. The candle wax will start to melt, and then, because of it's lower flame point, will burst into flame. Be aware it will happen, and don't get startled. The paraffin will consume itself almost completely (no ash), so be sure to stir whirlpools aggressively as soon as you can. Skim off whatever grit that develops, and repeat as many times as you feel that you need to to get to as clean as you'd like. I like to flux with paraffin wax 4-5 times. By then, the metal is pretty darn clean by my fussy standards. (including the pot surfaces, which I have been scraping the whole time)......

7) When using your ladle to remove the lead from the smelting pot, push the ladle through the surface of the lead, and allow the ladle to "back fill" with only shiny metal. Even though you have done this immense amount of fluxing, you will always see some additional crud floating to the surface as you ladle, and you want to avoid introducing that into the ingots you are making. The back filling technique with the ladle is the best way to keep the grit out of the ingots you are making. When you get to a point where the grit really starts to be a nuisance, and it will...... do some more paraffin fluxing.........

8) Continue making ingots until you get down to that 1" or so of lead left in the pot, and stop. Or, if you have more to smelt, stop making ingots when you have a couple of inches of lead still in the pot. That will give you the good lead puddle for melting.

Notes: Some folks have used motor oil as a fluxing agent. I have used it in tests and find it smelly and full of carcinogens. It works OK, but I still prefer to use the candle or store bought paraffin wax. The store bought version is usually sold in the jam making supplies area of the store. Comes in a one pound package of four blocks, and is very pure, and translucent clear. It's more expensive than cheap used candles. I'm already saving money making my own boolits, and I feel no compulsion to go extra cheap on fluxing agents. I want/demand very highly clean lead to run through my guns. Don't be in a hurry when smelting. It's hard on the back, and hot on a summers day. I find that by pacing myself in a slower pace, I get better alloy because I am taking care to flux well. You cannot flux alloy too much.......... You just can't. The more, the better/cleaner the alloy will be. By constantly stirring, you will keep any tin and antimony in the mix. You can't really skim out those metals, nor do you want to. However, if you stop stirring aggressively, and perhaps have the heat too high, you will allow the tin and antimony to come out of solution with the lead, where it will float to the surface in it's typical yellow/gold and purple hues. Don't skim off the yellow/golds or the purples. Turn the heat down a bit, and stir those back into the lead.

My advice has been primarily relating to range lead because that's what you asked about. The same process is used when I smelt clip on wheel weights. However, it's especially important to add weights slowly to the molten puddle to avoid accidentally melting in any zinc to the pot. Zinc will float, but only if you have added a thin enough layer to allow them to float. If you bury zinc weights under 60 pounds of lead weights, and have the pot too hot, you will get zinc contamination. So, my advice for adding new material to the pot slowly and in thin layers holds true whether for range lead or for wheel weights.

I've touched on many of the points that others have made, but I don't think anyone else has covered it as completely, in one place as I have. My system isn't perfect, but it works really well for me. I get good clean alloy. And, I know my bores (barrels) will have longer lives from the extra trouble I take getting the clean alloy.

Perhaps this post/thread might make a good sticky. I'd be happy to amend my post should anyone think of anything additional idea that would improve my system even more. We have many great casters here. And their system works for them. I take no exception to any of that. However, in my quest for CLEAN alloy, my system gets me there.

[Garyshome]

Now that's what I was looking for. Thanks for the post!

[bangerjim]

JW..............Good article! Glad you saved it for us.

banger

[JWFilips]

Well I'm a pack rat and squirrel everything away ( hopefully I will remember were everything is in a few years!) If I see good stuff posted for the public eye I grab it up because I find it very hard to use the search feature on this forum. In a few years when "Gear" forgets about his fantastic explanation of fluxing he posted a few weeks ago..... Well I have that saved too!;)

[rondog]

Awesome info! How do you save it? Copy/paste into Word or something?

[JWFilips]

Awesome info! How do you save it? Copy/paste into Word or something?
Yes that is what I do You can also go into "Thread Tools" at the top right of the first post and select "printable version" this will remove any background "fills" based on the style of this form you have chosen.

I had hoped it would have been made a "sticky" but the mods need to decide that

[leeggen]

JW guess I missed the fluxing by Gear, would it be possible to get it from you?? ERR atleast give up the posting, got a heck of a bunch of hits when I tried to find it.
Thanks,
CD

[JWFilips]

JW guess I missed the fluxing by Gear, would it be possible to get it from you?? ERR atleast give up the posting, got a heck of a bunch of hits when I tried to find it.
Thanks,
CD

I too just ran this forums search engine ragged to find it to post the link to the thread Just doesn't run it well

So Geargnasher I hope you don't mind me re-quoting your best explanation ever on the subject : :?:



Boolit casters typically use dirty, contaminated scrap from whatever source we can scrounge up, and that sort of stuff needs special attention to make the best boolits. Clean alloy like nuclear medicine shields or foundry alloy doesn't require as much cleaning.

We need to do three things to our alloy: Clean, reduce oxides, and flux.

Cleaning is accomplished by mechanical action, stirring and skimming dirt, sand, steel clips, rust flakes, copper jackets, whatever. A slotted spoon is adequate.

Oxide reduction is next. We need to deal with the oxide dross formation on top of the metal, whether in smelting pot, or a freshly-melted casting pot full of clean ingots. Boolit alloy dross is very rich in valuable tin, so we need to turn it back into useable metal rather than skim and toss it. The opposite of oxidation is a chemical process called "reduction", so if we induce a reduction/oxidation reaction on top of the metal, we can save the scum. Combustion is a redox reaction. Anything that will burn will trade electrons with the oxidized metal, sort of "stealing" the oxygen and freeing the tin and other metals from the scum so they go back into the alloy. Grease, wax, oil, sawdust, anything like that will work to reduce oxides, and if your alloy is clean of other contaminating metals waxes work fine for this job.

Now, about Fluxing. This is the part that seems to confuse everyone. If your alloy came from wheel weights or other dirty scrap, it likely contains a bunch of other metals that don't cast very well and mess up the flow, or FLUX, of the alloy. This makes it tough to cast good boolits. Things we want to get rid of are zinc, aluminum, iron, calcium, and a few others. Since what we want to get rid of is all pretty much more difficult to reduce than lead, tin, and antimony, we can remove it through adsorption. With a "d". Things that work really well at removing the oxides of contaminating metals are molten borate glass and the carbohydrates in wood. Wax won't do it. The problem with borates (such as Marvellux) is that they don't reduce any of the oxides at all, including tin, they just adsorb them and remove them from the alloy. If you want to save your tin/antimony/bismuth/lead oxides, use sawdust because it saves the good stuff and adsorbs the bad stuff so it can be skimmed and thrown away with the ash when it has finished burning.

So again, sawdust, being a hydrocarbon, will also reduce tin/lead/antimony oxides we want to save while adsorbing the remainder of the junk we want to remove and capturing it in the ash. Two for one, so to speak. Resiny, pine sawdust, particularly sappy yellow pine, is one of the best reducant/fluxes I have ever used because the resin is such a fine and quick sacrificial reducant, quickly reducing the good stuff so it won't get adsorbed, but leaving the oxidized trash metals for the carbon to soak up as the wood chars.

Sawdust and ash cannot get below the surface of the melt and cause problems unless you drag it down there physically so that it gets trapped below the surface tension of the alloy at the bottom of the pot. Carrying ash down there on the end of a fresh ingot, a handful of sprues, or by scratching around on the bottom of the pot with a wooden stick are the principle ways of getting ash junk on the bottom where it will migrate to the spout and cause inclusions in the boolits. Use common sense and it won't happen. A wood stick is the bee's knees for scraping all the stuck, baked dross off the sides of the casting pot, it reduces oxides on contact.

Gear

[harley6699]

When I am smelting unknown source lead (WW, Range Lead, Boat Keels, etc..) I first melt it, skim then **** off the top and put them into ingots.. I don't flux it at this time.. when I am ready to cast I use Marvelux Fux.. this way I can use a smaller amount and I can controll it better then in a 40 lbs pot..

[Boyscout]

I would do a hand sort of your lead before melting. The last 3 buckets of lead I have gotten were about 60% COWW/SOWW-40% Steel/Zn. That is a lot of unwanted material to skim. Also, I don't want any zinc to get in the pot if I can help it. Dittos on leaving a puddle and starting with that the next time. I also add slowly, skim, and add again. I seem to lose too much lead with the clips when I have to remove too many at a time.

I would recommend at least one cleaning with sawdust and wax before pouring your ingots. I run small batches in my bottom pours (10 & 20 lb Lees). I run a wide variety of ingot sizes (Lee, Lyman, Wilton Muffin pans) and weigh out my proportions, melt them and mix my alloy for immediate use. I read smelting in a bottom pour is rough on them. If I start with clean ingots, I don't have to worry about contaminated alloy and inclusions in my cast.

It's a lot easier to do the cleaning in a smelting pot than when you want to start a casting session. Spending the extra time up front will save a lot of time later. I do ingots in WW+2% Sn, Alloy #2, SOWW, and pure Lead. Wheel weights I usually don't stamp. Everything else gets the Harbor Freight punch treatment: WW, #2, SO, 15. I don't melt my Lino and Foundry-type into ingots as they are clean and in a perfect form to weigh out for alloying.