Please Help Smelting Issues WW

[Unlucky1]

OK, this is driving me crazy as if I am not already there. I have a cast iron pot with a fish fryer burner running off of propain that I fabricated a fid controller into my setup to keep my temp at 650 and it will also alarm me if it hits over 700. I am smelting wheel weights, lots of junk in them. I start with some already semi clean ingots that are wheel weight material too, to start my brew. I add wheel weights of all sorts to the pot (remember that I do not get over 700 without the neighbor telling me I have a smoke detector or large concrete truck backing up behind my garage (lol). Once the added weights get to 650 again, I scrape and scoop all the steel and zink and gargage out and scrape and I even bought a wire brush contraption for a grill that i scrate the bottom with too. I then add more wheel weights and do it over again. Once I have a pretty full pot that I have stirred and scraped and cleaned multiple times, I throw in come saw dust and light it on fire and stir and scrap again.
Ok, now you know my process. Here is the problem. If I dip out of the top, every time I put the ladel into the pot I get crud forming on the top. I scrape and clean and it come back over and over again and again. then when I poor my ingots, they have what looks like dirt on the bottom side (stuff floating to top when poored into ingots). If I use the newly fabricated bottom poor I get the same results. (P.S. It leaks a very little, needs more work). When I got to the bottom of the pot(I emptied it to see if there was crud on the bottom) it was pretty darn clean. Suggestions please. Pretty please. Just my 2 cents that has not panned out yet was that something colder than the lead entering the 650 degree pot may be whats causing the stuff. Can it be off my ladel? I did try two different ones, and I can not swipe another from the house without the wife ending my reloading career. I am attaching a few picture to let you see the stuff I am talking about.
NOTE: The shot of the top of the ingot was just to show you that it is not to bad on top. The pics of the lead with dirt or whatever floating in them, do not worry about the unevenness, that was me not filling evenly. I will work on my pouring skills but did not really care as I want these clean and will probably do it again after I figure out how to get rid of the crud. you can see the crud on the spook I use to cleand and scrap with in a couple of pics.
Thanks in advance,
John

[waksupi]

That film you are scraping off, is most likely your tin. Put it back in, and stir the pot with a dry stick.

[David2011]

Hi John,

Welcome to the forum!

You might try topping out your temperature at about 650 degrees. Zinc wheelweights will melt at 700 or so. Pure zinc melts at 787. You may have a little less separation of the good stuff if you lower the temp, too.

No need to start with ingots. Your smelting setup will melt WW just fine. No need to do all the scraping IMO. That can keep garbage stirred up that you're trying to avoid. The photos look like you're using a large kitchen spoon rather than a ladle. There's a difference. At any rate, let it get hot. That will keep the melt from adhering to it. It looks like the tin and other good stuff floating on top is being skimmed by a cold tool. It will also help burn off any contamination to let it get up to the melt temp.

I noticed a one piece stainless steel bowl type ladle on a hanger in Wal-Mart today that was pretty inexpensive. The handle and bowl were stamped from a single piece of metal. The ones that have the handle spot welded with two tiny spot welds are fine for beans but the bowl can break off if full of molten lead. A real ladle with a bowl will allow much smoother pouring. You can get a perforated serving spoon at Dollar Tree for a buck and that will make skimming much easier than using a solid spoon.

How much sawdust are you using? The entire surface needs to be covered thick enough to exclude air so you can stir in the tin and antimony that are separating. The WW I've gotten is usually oily enough that the oil works to help flux. There was a thread just a few days ago that went into great detail about the differences between fluxing with oil, wax and the like versus sawdust. Maybe someone can remember and post a link back to it. It was very good.

I've used Borax, candle wax, boolit lube and parrifin to help clean the metal while it's melted. They all seem to work about the same for me. I'm less experienced with sawdust but will have a good supply after finishishing the construction project in my workshop and will try it some more to see if I can tell a difference. Borax must not be allowed to sit in a humid environment. even overnight. It will absorb moisture and can cause a steam explosion that will violently spray molten lead in all directions if forced into molten lead. (See "Tinsel Fairy".) It's best to store it in an airtight plastic ontainer if you decide to use it.

Keep us posted.

David

[runfiverun]

it's the black powder that's giving him the problems.
it just don't have enough heat currents to ride to the top.
try cutting down on the amount of carbon [sawdust] you use.
brake dust will settle out of ww's too, i can dump a bunch out of my smelter when i am done.
i just keep pushing it out of my way and try cherry picking out the best alloy from the pot.

just plain ol stir and scrape and stir and scrape will pull a lot of the dust to the top.
skim it off and toss it yeah you'll sacrafice some alloy.
i also turn the heat up on my alloy to the 775 or even a bit higher range before fluxing just to get things mixed in.
i turn the heat down as soon as i start the flux, returning it to the lower temp, then do the scrape stir thing.

[Unlucky1]

I am aware that lead metling point is aroudn 620 and zink i believe is 780. Thats why I set my pid controller at 650. I have a regular ladel that I use to actually pour the lead into the ingots with. that spoon you see with the gunk on it is the one I use exclusivly to just scrape off the dross. I have seen people say that yo uhave to stir back in the good stuff before. I thought antimony had to get super hot to mix/unmix and as for the tin, I am not sure but if it seperate from the lead at 650 or 700, I would imagine most people would lose their tin mixture in their lead. I can not leave a pound of saw dust on the top as the whole idea of making ingots is to use the saw dust or candle wax .... as a tool to combine with the things you do not want.

As for the second reply, you may have a good idea to try. Once I get the majority of misc. link, metal, burnt oil, and who knows what else out, I should be able to crank up the temp. I went to a great deal of effort to build a pid controller to control my lee botton pour pots temp and also use it to control temperature of my smelting pot. I went a little high tech and a bigger smelting pot and thats probably where the issue lies. I the past, my temperature fluxuated a ton and I had to sort every zink wheel weight out of 5 gallon buckets. Well, we all know how horific that can be with the time it takes and all the nasty stuff on them. And you always miss a couple. I am guessing that before I was able to control my temp well and had a cast iron skillit instead of a cast iron pot 4 times the size, I was cooking it pretty hot at times. I also used to flux with candle wax and I switched to saw dust because of these issues. I have always had a little dross on the top but now I have a ton every time I did my stainless steel ladel or my scooper or whatever in. Apparently the temperature difference with the ladel into the pot makes the gook clump up. Thats not really a bad thing if I cold control it. It just comes so fast that I can not get it out of my way. I even went to my dollar store ladel that is about 5 times the size of a big spoon. Its terrible to use because it does not even hold a pound of lead. On the flip side, maybe I need to try to lower my temperature as well. If the stuff is solidifying when the cold hits it, maybe cooling it down to 620 or 600 and stirring it up a little may get a bunch out. I will try a few things and let you all know. Keep the info comming.. I appreciate it. Right now, its a weather issues of when I can smelt without those exploding drops of water falling on my head and in the pot. It was about 45 here today I think (indianapolis, in area) and a great day to smelt. I now have probably 200 lbs of smelted lead that has crud in it that I will have to smelt again. i just keep adding to my pile but at least they are not wheel weights any longer!! heehee.

P.S. I have been reading about things to flux with for months now. I think everyone has a different opinion. I hae even heard flux is a waste of time because you have plenty of things in wheel weights that will create it's own flux. I do not mind throwing in a chunk of candle or some saw dust if it may even help. No big deal on that. If all else fails, try everything. LOL

[Defcon-One]

Honestly, your pics tell me that you're doing everthing right. 650-700 is perfect. I flux at about 700 then reduce to 650 to reduce the the skin on top and pour my ingots.

I don't see a bunch of specs or scum, just a bit of oxidized metal which is pretty normal. As it sits more will accumulate.

I flux with sawdust and aggressive stirring, then skim and cast ingots. Any minor particles that get in the ingots are fluxed out in the next step before casting bullets. For me, smelting is just to get the wheel weights into usable, fairly clean lead ingots, no clips, no trash and no zinc.

You appear to be doing a very good job of that!

DC-1

[dragonrider]

I see nothing wrong with your process except that you are spending too much time scraping and tossing. And your ingots look just fine. Your first flux should be done before you remove the clips. I use sawdust by the handfuls when fluxing during smelting,. I let it char completely, then I use a ladle and lift out ladlesful and pour it back in, I lift from the bottom of the pot, I do this repeatedly. I then remove the junk, clips, dirt etc, and then repeat the fluxing, add sawdust, let char completely, when it is smoking good I lite it on fire that speeds up the charring. Scoop and pour over and over again. Then clean out the crud again. WARNING never push sawdust below the surface of your melt until it has completely charred, no matter how dry you think the sawdust is, IT ISN'T DRY ENOUGH unitl it is charred.

[I'll Make Mine]

Try to separate the zinc weights from the lead before melting. Although zinc melts at a significantly higher temperature than lead, it will dissolve at around 2% by weight at lead melting temperatures; that means any ingots you've made with zinc weights in the pot are zinc contaminated. Zinc is antagonistic to tin and antimony, so it may contribute to bad stuff forming on your pot or in your ingots; it may also lead to stratification of the melt that, if carried through to casting, may cause unbalanced boolits (zinc is about 2/3 the density of lead, so if it crystallizes first, it'll make a lighter grain that will have similar effect to a small void).

I'm about to start sorting my first bucket of wheel weights, but the technique I plan to use is to pick out weights I'm sure are lead in the common sizes (1/4, 1/2, 3/4, 1 ounce, etc.) to use as exemplars, and if I get a weight that's marked in one of those sizes but is physically larger, it gets rejected as probably either zinc or steel (steel won't hurt your melt, it just has to be skimmed out).

[375RUGER]

+1 on raising the temp to flux. Start with the low heat if you are worried about the zinc weights. get it melted and get the zinc out if they exist. then crank up the heat and flux the dickens out of it. you can turn the heat right back down just before you flux as that lead will hold heat like, um cast iron anyway.
I personally don't remove the flux from the top of the melt, I push it aside and get a ladle full and pour, because the pot will be sitting waiting for ingots to cool before I dip the next batch.

Don't make the process more complicated than it has to be. You're off to a better start than I was when I started.

[yarro]

I pull all the zinc WW out first. I don't get many zinc ones as my brother tries not to put any in his bucket at work, but occasionally someone else tosses some in. I still sort through them all though it is dirty work. Most of mine are large sizes used on the retreads from the trucks/trailers at his work. I used to get a lot of WW, but now all the guys that work with him keep what they take off to sell and supplement their pay.

-yarro

[runfiverun]

the sawdust isn't fluxing it is carborizing.
adding carbon into the alloy which allows etter chemical bonding of the alloys contents.
which helps prevent oxidization of the lighter components.
you need an oxygen free barrier to properly flux a lead alloy. [return the oxides back into the alloy]

[badbob454]

your ingots look good enuff dont sweat it .. you are using a bottom pour so it dosent matter what is floating on top
proceed with your casting and dont look back ...

[shadowcaster]

the sawdust isn't fluxing it is carborizing.
adding carbon into the alloy which allows etter chemical bonding of the alloys contents.
which helps prevent oxidization of the lighter components.
you need an oxygen free barrier to properly flux a lead alloy. [return the oxides back into the alloy]

r5r has an excellent point here. Also, your cleaner lead is at the bottom of the pot. I have all but given up using a ladle for this very reason.
I'm not sure what the elevation is where you live, but here at 2900 feet I find that I have to run my bottom pour smelter closer to the 700 degree range to keep the lead molten/fluid. At 621 degrees it's still a bit slushy.
For ease of pouring and purdy ingots I preheat my molds, just like when casting boolits. Your ingots look fine. You are never going to be able to make ingots that are perfect 100% clean. It's just not realistic. I flux and stir/scrap again in my casting pot just before pouring boolits.

By the way, excellent job on the bottom pour smelting pot!! :cbpour:

Shad

[Lizard333]

I second that your skimming the tin off the top of your part. Flux like normal and pour it into ingots. Your doing fine.

[Unlucky1]

Every once in a while i hear the people are pulling the tin out of the lead. What castes that? What temp does the tin melt at? I would think it would not seperate unless you get it hot enough to melt the tin and it floars to the top. Second question is covering the lead to keep down ozidation. Suggestions on that? Do you think the oxidation is causin the gook that is comming up? I have also heard/read to stir it back in. The stuff comming up does not stir back in, i have tried. It is lighter than the lead and floats to the top both in my iron pot and ingot molds. Just curious. I certainly do not want to offend anyone but it sounds like lots of guessing with this process and my logical thinking say s it has to do with teperature to cause seperation of contaminents to get them to the top and possibly something to bond to the contamament to get them to come up. Sorry all, mr pure logic here I am trying to underst and to make this closer to a science as i know it mest be when they make wheel weights with recycled material and especially car batteries as adding acid to dirty lead would cause a ton of gas as the junk disolves/get burnt up by the acid. Thanks again and keep it comming. I do understand the i will flux again in the melt but trying to get. As much crud out as possible. Thanks again all. I do appreciate everyones info!!!!

[Lizard333]

I guess to answer your first question tin, Sn, melts at 450 degrees Fahrenheit. It will float on top of the lead if not properly fluxed.

Your pot of lead will begin to oxidize without a proper oxygen barrier. I personally use saw dust. Have you ever noticed the white powder that forms on very old pieces of lead?? Some people are using kitty litter. Works just as we'll.

Personally I keep my pot at the lowest possible temp to prevent oxidation of the lead, prevent the tin from separating, and to prevent Zn WW's from contaminating the pot.

[Defcon-One]

Sorry to be blunt, but your instict is wrong. Tin does not float out of an alloy. It oxidizes out, but not very quickly and not very much at casting temperatures.

My advice is correct. I'd follow it. But you can do what you want.

Instinct and science are just about opposites!

[Unlucky1]

It ozidizes out makes the most sense to me because it would be impossible to stir it back in and expect it not to come right back to the top. P.s. i love blunt and to the point myself. So, i nees a barier to keep oxigen from my lead when it hot. This has nothing to do with the flux process correct? Would i cover it with non burnt saw dist ir kitty litter(clay) to keep the ozigen out or burn sawdust ( a bunch to coat the top?). Next dumb question, all the stirring and scraping to get dross/crud out would intruduce more and more oxigen correct? Next. I would strictly have to use it as a bottom pour to get around the layer or whatever i make the barrier out of correct? I would not ask that but i need to rework my bottom pour design as the screw sticks and it leaks a little. I have plans to just have a hinged needle valve that just sits in there but no got that far yet. I am opporational with the bottom pour but uncomfortable with the tork it can take to loosen the screw when it gets hot( but that anoth subject). So do you rhink the black llooking powger that nevet stips commin is oxidizized tin, ghat may explain the disclloration or tim if thats what it is. Thanks all for everything. I know we have had about 5 or so kind conflicking answers and i hpoe we are all in agreemebt when resolved. P.S. is the kitty littler a mess to clean out of the pot?

[454PB]

There's a lot of opinions here....here's mine. Your ingots look fine. Tin cannot be separated from the alloy other than by oxidation. If it was possible to separate the various elements in the alloy, you could remove any zinc that was there. I tried that once, letting a pot stay molten for several days and then fluxing and skimming the top every 8 hours or so........it didn't work, all I removed was dross (oxidized metals from the mix), and the alloy was still zinc contaminated.

The black residue you are seeing is dirt....brake dust, cooked rubber debris, and cooked grease from the wheel weights. Most of it rises to the top while you flux, but some is always found in the bottom of the smelting pot.

[Springfield]

Just a rule of thumb that I use. When using sawdust to clean the lead, the lead temp shoould be right around where the sawdust will burst into flames by itself. If lower I find it just doesn't work as well. I also like to sometimes mix in a bit of beeswax in the sawdust, sometimes it helps, sometimes it doesn't but it never seems to hurt. I only smelt about 2000 lbs a year so take the advice for what it is worth. I would also take out all of the larger pieces and non-lead weights and then turn up the heat a bit for proper cleaning. Also, if the sawdust isn't ash, it isn't done yet.

[Gtek]

Here is my routine. I have 50 lb. pot and must have big slotted stainless spoon. 680-700. melt,stir, skim, stir, skim, stir, skim, stir, skim. Scrape sides and bottom up, stir, skim, stir, skim. Stirring to the point of swirling pot, junk floats to top center and lift out. When pouring ingots scoop from bottom up not touching pot, little stuff will float off on lift out. Run down to a half an inch or so and place bent wire in pot and let cool. If going again no wire but let top solid off to keep tinsel fairy away when refilling for next go. Placing wire allows you to lift out for alloy change or cleaning pot. Also starting with solid pancake in bottom gets you going a whole lot faster when re-melt starts. I also have 1/4" alloy plat made for top of pot with hole for thermo, glad I made that also. You are fine tuning at this point. OOPS forgot, you might find life a little easier not filling to point of joining sections. Yes more pieces- but easier to change alloy mixture on future melts. Welcome to the madness! Gtek

[Unlucky1]

Well, if the weather holds out, I will go at it again. I have to get more ingot molds!! I only have 3 lee ingot molds and about 50 lbs of lead. Its painful to wait for the ingots to cool. I am going to make some out or angle iron I think. That is the biggest slow down that I can do anything about right now. I will try many of the iseas in the posting above and have already done a few in the past. One way or another I will do some more smelting this weekend or before. As you all know, it's a small project to drag out everything and go for it and I like to do at least a pot or two when I do it. If any of you have any great ideas for making cheap ingot molds that will fit in lee pots. I have seen a few and I do have a mig welder (my welding skills suck but this would be a great thing to practice on). I was simply thinking of 1 1/2" angle iron with the V down and cut them on an angle for easy release and use the same angle for the sides to close the ends up and five me two handles. I am open to CHEAP suggestions on molds if anyone wants to throw something out there for me. I 3 lb molds just arent cutting it. I did cupcake pans and hated it. Many would stick and just a huge hastle but I think I can make nice sized (not to big) molds for the same price as the lee ones and definatly cheaper than the rcbs ones (that hold more lead). Thanks! I will keep you all updated. When I get time and energy, I will post my propane fish fryer design and electronic temperature control using a pid controller. I had probably 100 bucks, I am guessing in it and it works awsome and I use it for my lee casting pot and my smelting pot. Its universal. Keep an eye out for a post. Hopefully I can get some picks out there this weekend for everyone.

[Gtek]

If you are in a hurry, thick steel ingot makers stay hot for a long time. Alloy seems to work the best for me. For cooling molds on I have a 1" angle set up cut to 12" edge to edge (washboard) welded with corner up, a 1" aluminum plate to flop on. Plus put a fan 45 degrees behind you to catch just above pot for fumes and hit ingot mold on backside. You will figure out what is best for you. I have three Lymans and it is just about perfect round robin. Gtek

[shadowcaster]

I use these cast iron wedge pans made by Lodge. I use 4 of them in rotation and they cost me 12$ each at target. The ingots fit perfectly in my set of Lee's pro 4 20 pound pots and weigh approximately 2 pounds each. By the time I fill the last pan, the 1st one is ready to dump out and they never stick.

http://castboolits.gunloads.com/imagehosting/thum_194224f542356303f5.jpg ('http://castboolits.gunloads.com/vbimghost.php?do=displayimg&imgid=4263')

I set them on a cinder block while using my bottom pour smelter for ease and control as the pan gets heavier while you fill each ingot mold.

Good luck.. :)

Shad

[454PB]

Here's one of the ones I made. It's made of 2" X 1/8" angle iron, the ingots weigh around 3 lbs., and fit right in my Lee casting pots. I did the welds on the back side to avoid grinding.



http://castboolits.gunloads.com/attachment.php?attachmentid=5060&d=1191949259

[runfiverun]

that looks just like the one i made but i used 1-1/2" angle iron.
and made it an 8 gang.
i can eyeball my ladle and get them just barely at 2 lbs.
you wanna tack weld everything [all the corners],use just barely enough heat, and do short welds spread out,or it could bow in the middle.