Crusty Pot

[Cabrilla Grande]

I figure a picture is worth 1000 words so what am I doing wrong here?

I did try to flux it... here's what I did. I got some paraffin wax and threw it in there. It flamed up within seconds and I scooped the black sooty looking junk off the top. I did this several times but this crust keeps on coming back. I even tried a big piece of wax and it boiled over the top. It looks almost like powdery rust or something but the pot isn't hot enough to melt iron?? Sulfur maybe? I don't think it's zinc because zinc oxide is white? I dunno what's going on.

I put like 2 lbs of old sinkers in there and 6 lbs of fresh lead from rotometals. Is it contaminated too badly? Do I need to start over with fresh stuff? I had to drain it out and clean it because it clogged the nozzle today when I was messing around. Do I have it too hot? I had the pot cranked.

I also have one related question: Has anyone ever tried to drill out the nozzle on their bottom pour pot to make it flow faster? Even unclogged it doesn't seem to pour fast enough.

This noob would appreciate any help.

Thanks.

[mkvnmtr]

That looks like powder that does not have much weight. I get that sometimes with fairly clean lead. It is much better than having zinc in the mix. I would not like to deal with it in an electric pot. I do all my lead cleaning on a gas burner in a bigger pot. Then I just scoop the powder off. As you are doing flux, flux and flux again. It seems counter productive to use a lot of wax at one time. I have had that kind of powder in large amounts on some very good lead. I am pleased to have it because it never seems to reach 1% of the weight of the lead. What I find to be a bigger problem is when a little zinc gets in the mix and the slag lose goes to 5 to 15%.

[Ogajiga]

I second that scrap lead should be pre-cleaned in an open pot & ladle setup before being used in a bottom pour melter. Poured into ingots and stored separately according to type and source. Mixing Roto Metals lead with mystery scrap is a waste of expensive foundry grade metal. Tackle castings don't usually require foundry purity, and wheel weights and cheaper scrap soft lead are generally adequate for our needs. The RM lead might be useful for a mold that won't pour with "normal" scrap based alloys.

Scrap sinkers could be contaminated with dirt, rust, salt, zinc - anything really. Since the hotter the melt the greater the slag formation the excessive amount of powdery dross could be a combination of lead contaminants, excessive heat, and wax residue. I sure wouldn't want that crud in a bottom pour melter.

So, CG, your solution could include using only clean lead in your melter at the lowest practical heat setting for the job.

Edited October 31, 2010 by hawnjigs

[Fatman]

I'd say your old sinkers were really dirty, I've done the same thing when Vermont made sinkers less than 1/2 oz illegal to use I melted them down and while not as dirty as what you show it was still dirty. I'd get a paint stick, cut it in half and use it to scrape the sides and bottom of the pot then use an old spoon to take the dirty stuff out. Reflux a few times and it should clean it right up.

I've been using my bottom pour since the 1980's to clean my lead and it's still going strong. I would NOT drill out the pour hole, I use an old jig with the barb cut off and bent into an L shape and I push it up into the pour hole and it usually takes care of it.

I do agree with Hawn, keep that batch of lead separate and use it all up. Then start with fresh lead.

Fatman

[Ogajiga]

Hey Fatman, do you put wheel weights directly into your melter? If you're cleaning lead in your bottom pour how do you deal with sinking powder dross?

[toadfrog]

My two cents and experience after many years . DON't drill on the pour spout. Not enough heat , to low on lead or dirty lead is the only real reason a pot won't pour. If you drill it it will leak forever. I can tell buy the dross in you pot you got some nasty crap in there. Sometimes old lead from batteries are use by folks to make sinkers . ITS HAZARDOUS. Not only will it eat up the inside of the pot it will ruin your lungs. Take it all out . If you have a way to smelt it outside do that . get it hot as you can , stir it with an oak dowel rod. Skim off the dross (Do not breathe the fumes) . Keep doing that untill the only thing you can skim off the lead is black soot from the rod. May take a long time and alot of heat. An old cast iron pot is best for this. Hope this helps.

[Cabrilla Grande]

Thanks for the tips guys. I cleaned out the pot really good then I lowered the heat setting like was suggested and it made all the difference in the world. I didn't get any more powdery stuff formed, just the black sooty stuff when I fluxed. The wierd thing is I used the remelted sinkers before trying to add the fresh metal and it didn't have the powdery crust problem at all.

[Fatman]

Hawn

Yes I do with my one bottom pour. I just keep scraping the sides and bottom and get out as much as I can. As I've posted before I had NEVER fluxed my lead and when the thread came up on it I tried and thought it was great!!!! Now I always do it.

I'm probably one of the few who ALWAYS emptys my pot after I'm done and clean it really well, just my preference and then I'm ready for the next time. My pot looks beat but I sure as heck can't complain I've really gotten my money's worth.

Fatman

[Long Lake Lures]

I saw the same thing after a year of pouring with mystery lead bought on ebay. I wasn't aware of the forming crust (around the wall on the bottom ) until the spout started clogging. I now do the same as Fatman and empty out the pot after each use.

Dave