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jonp
12-06-2018, 10:56 AM
I have a large stainless bowl that I use when I melt wheelweights, scrap etc to hold the dross. I was looking at it and noticed metal so I decided to remelt and pour some ingots assuming I wasn't paying close enough attention or stirring in enough sawdust. I got 4 bright and shiney ingots and nothing but dust left over on this secong attempt.

When I put my Lee tester on one it came out
7.7 BHN.

Lead is 5, tin 7 bhn and antimony 50 bhn or so. I expect them to harden a little more and with this in mind anyone care to take a guess?

Tin with a little antimony? I just cast some boolits from 2 containers. 1 COWW and one PB for a 50/50. After 2 weeks their BHN is 14.7 so obviously something not right there. :-(

lightman
12-06-2018, 12:27 PM
I'm guessing tin and a little antimony, like you guessed. I would keep those ingots separate and melt them into the next big batch that you do. Fluxed properly, all you should get is ash looking stuff and any lighter metals like wheel weight clips, bullet jackets or dirt.

Grmps
12-06-2018, 01:57 PM
I use and love pine sawdust for fluxing, but, I have found that my fluxing is never complete unless I do at least 1 flux with wax.

Wax gets/does something the pine sawdust alone doesn't do.

I haven't seen much difference between paraffin and beeswax so now I just stick a candle in the molten lead and wait for the desired sized puddle to form.

Budzilla 19
12-06-2018, 02:15 PM
+1 on pine sawdust ( the real stuff with lots of rosin)and paraffin!!! Multiple times sawdust, then 2 times with wax, I agree wax does something sawdust doesn’t. Boy, that sawdust smells sooooooo good! Just my opinion

LenH
12-06-2018, 02:49 PM
I use aspen pet bedding along with a good chunk of wax or bullet lube that I no longer use. I will throw a healthy bunch of the pet bedding and then
throw in the wax and then light it when it starts to melt. It burns like crazy and it seems to do what others above have written.

jonp
12-06-2018, 07:36 PM
I normally do the pine bedding a couple of times to the raw coww or scrap followed by paraffin. I'm not sure what I did to the original. To the dross I used beeswax I had left from an order I put in to RandyRat that my wife made candles out of, lit it up then stirred. I can say it smelled much nicer than the pariffin.
The metal went right into the melt and nothing but dust left on the top.

Shiniest ingots I ever poured. :-P

I guess my point was that it pays to melt your dross one more time just in case you messed up like I did

beagle
12-08-2018, 02:35 PM
A friend once melted a load of #9 shot for lead (back when shot was $6 a bag). We ended up with about three 3# coffee cans full of skimmed alloy off the top. I got several cans and used it to slightly harden WW alloy. Must have been pretty high antimony/tin alloy./beagle

Silvercreek Farmer
12-08-2018, 03:16 PM
A while back, I smelted all my dross, mostly from WW. The resulting alloy was certainly different from WW. I got around 5 lbs of alloy from a gallon or so of dross. As suggested, I mixed it back into a 50 lb batch of WW. It'd be interesting to see what it tests out at.

Lloyd Smale
12-10-2018, 07:59 AM
you got oxidized lead, tin and antimony. Same thing that's. one or more of them may oxidize a bit more but if you tested it it would contain all of them

uscra112
12-10-2018, 09:23 AM
If you got that much metal out of your collected dross, you're not doing your fluxing thoroughly enough. There shouldn't be ANY metal in your dross.

Petander
12-19-2018, 11:36 AM
you got oxidized lead, tin and antimony. Same thing that's. one or more of them may oxidize a bit more but if you tested it it would contain all of them

Yes.

I"m lazy fluxing when I"m casting and there is metal in my dross. I usually have some monotype in the mix.

I added some if my collected dross to an ingot melting pot and my pure/ww - mix came out 18 BHN, tested 12% antimony 3% tin. The antimony/tin -dross made it hard.

RogerDat
12-21-2018, 03:38 AM
My dross bucket has skimming from casting, once I get started pouring ingots I will just stir with flat wooden stick then skim surface to clear and scoop out whatever doesn't easily work back in. I also have spatters, drips, stuff I pick off of tools and pots. Really if one is doing a hundred pound or better batch then allowing a pound or two to end up in the dross bucket in order to keep a good work pace going is no problem.

Every so often I take and melt the dross and assorted "stuff" by putting in dutch oven in small batches and crushing with a 2x2 like a mortar and pestle. Builds up molten metal in the bottom of the pot, skim off just fine ash and pour a bread pan slab of recycled lead to include in a later batch. Think I have about 15# or 20# of those 3 or 4 pound slabs built up. They will be at least WW and better so adding one to a 125# batch of WW lead works fine. Melting lead out of the dross is also a good way to heat the garage up a bit during cold weather while I'm working in it. I cast at same bench the fish fryer burned is on. Gives me a reason to have it fired up.

GregLaROCHE
12-21-2018, 04:23 AM
When processing range scrap, I find it difficult to remove the dross, without getting a bit of lead from the surface. I once ran a five gallon bucket of dross and got a few more ingots. Not sure if it was worth the time and propane though? I never thought it would be a different alloy than the original, but maybe so.