Lead Media Casting

[Mumbles]

So, I did some lead casting experiments today. I cast some milling media in copper tubes. They were 3/4" ID and 6" long. Aluminum tape was added to the end to keep the lead inside. The tubes were propped into a large flower pot in soil. I have heard many people having problems with casting it into copper and being able to get it out, via passfire method. I don't consider it anything Kyle invented, or was the first to come up with, so I will go into detail into the proceedure. I also tried using paper and aluminum foil tubes. They had paper innards and an aluminum foil outter to keep the lead in the tube. I don't think the paper did anything, it was chared as fast as soon as the lead touched it. Just Al foil would be fine.

 

Background:

I tried 2 different factors; length of cooling time, and use of a mold release agent. There were two tubes for each test, to make sure there wasn't just a fluke in one tube. The long cool time tubes were allowed to cool for approximatly 5 hours, though 3 would have been sufficient. The short cool time was allowed 20 minutes, and then dumped into a bucket of water to complete cooling. The mold release agent was vaseline thinned with mineral spirits. It was painted on the inside of the tubes. Two mold release tubes were cooled short, and two were cooled long. The mold release agent was used to help get the lead from bonding to the copper tube, and assist it coming out.

 

I don't have a bandsaw, or anything that can cut metal so I had to do it by hand with a hacksaw. You CANNOT cut the tubes with tubing cutter. They put burrs on the tube that are hard to remove. It also compresses the end a bit, which could make the lead sieze. After the tubes were cut, they were deburred and smoothed on the ends with steel wool and a sanding sponge.

 

The lead ingots used were of the linotype variety. I got about 50 pounds of ebay for about $30. The lead was melted over a charcoal fire in a stainless steel bowl aquired at goodwill for 50 cents. A stainless steel spoon was also acquired from goodwill for 75 cents. I bent it up to be able to hold more, and form a pouring spout.

 

If anyone cares to repeat my experiments to verify my findings feel free. I suggest a few safety precautions. I used a respirator with filters that protect against lead fumes. It says so right on the package. I also used welding gloves to protect from the heat. Well, they wern't technically welding gloves, but they were asbestos gloves Long pants and sleeves were used.

 

Proceedure:

 

The lead was melted in the pan on a charcoal fire. After melting, it was scooped into my pseudoladle and poured into the tubes. Multiple additions are fine as long as the lead does not solidify between additions. I had this problem when I ran out of lead. You essentially do not get multiple cylinders in the same tube as they do not fuse. This could perhaps be used to prevent having to cut the tubes later, but its a lot easier to form them all, then cut them if you ask me. When the lead was added to the tube with vaseline mold release, it sizzled at first.

 

After the cooling period(20 min or 3 hours), the tape was pealed off. Coincidentally, the ones that were coated with vaseline had the tape peel right off. The non coated ones stuck pretty well. I could press the lead out a bit with my thumb, which is good. It means it didn't bond to the copper itself. A dowel smaller than the ID of the copper is placed into the tube and rammed against a hard surface. I used the concrete basement floor.

 

Results:

 

S - short cooling

L - long cooling

V - vaseline

D - Dry

 

SD - One tube siezed, and one came out. It was hard to get the lead out of the copper. I had to let some of it solidify as I ran out of lead.

 

SV - The lead came out very easily. The lead didn't stick to the tape. The lead was a bit oily from the vaseline. It took maybe 5 hits to get it complrely out of the tube. I could press it out a bit more than 1/2" with just my thumb.

 

LD - This was shitty. I got them out no more than an inch and a half with the pounding. Both siezed up.

 

LV - These came out fairly easily. They needed more strikes than the fast cooled. It still came out fairly easily. It is still oily. It stuck to the tape more than the fast cooled ones. I found this odd.

 

Results:

All in all, I think it is obvious that the vaseline is helpful and neccesary. It keeps the lead from sticking, and assists it in getting out. The extra 10 seconds per tube is well worth it. I'd suggest a fresh layerr of vaseline everytime. It will allow your tubes to be used over and over again without worry of having to cut the tube, or melt the lead out. As the lead came out, there were some scratch marks down the sides, probably not perfectly smooth or circular ends scratched the lead. One other thing I noticed is that fast cooled lead was more brittle, I could snap some lead that fell down the side. I don't know how this will affect the final media

 

Feel free to offer any comments or questions. I think I covered everything pretty well, but I probably missed something.

[chappers]

You should be able to reduce the cooling time down to seconds really I make a lot of fishing sinkers, roughly the same size as you did in your experiment, and they can be turned out almost straight away.

[Mumbles]

I just wanted to let it solidify first before quenching with water. I didn't want the lead to deform or flow from the tube as they are just dropped into the bucket. The water still boiled pretty good from the tubes being added even after 20 mintues.

[Canadian_Pyro]

I dont use lead media, due to the fact that it will leave lead dust in you comps. I dont care if it is tin/antimony hardened, it will still contaminate. Lead dust can be inhaled where it will be absorbed into you bloodstream, slowly accumulating in your body, causing mainly neurological effects. It can also pass through the skin, but with differing effects. Lead oxide smoke is not a good thing to breath either.

 

Go to a scrap metal dealer and buy enough brass round stock to properly charge your mill jar. 15 feet of 5/8'' round stock chopped into 5/8'' lengths is enough to fill a one gallon jar. It cost me 30 bucks, because the stock was severely bent and scared, hence the word scrap. Worked fine none the less. Now you will never have to deal with toxic BP again.

[Mumbles]

First of all, I'm not scared of lead in my comps. A tiny bit of lead in the smoke is the least of my worries. Secondly I will have multiple types of media. People had been having problems getting the lead out of the copper tubes. I was mearly offering a solution to try to help them out.

 

Brass is not quite the miracle media either. Brass is much more easily corroded than lead. It is corroded by dichromate, sulfur, and possibly things containing iron oxide. It is also less dense. I am also not completly convinced of it's not sparking properties. Some alloys contain materials that can spark. It is completely incompatable ammonium salts. Do you also not think that the brass will leave brass dust in the mixtures? Copper and zinc arn't exactly good for the body either(in the form it would be absorbed in). Some alloys contain arsenic, which would be fun for the body. Brass also brittles over time from use, and may crack or deform. It is not so easily recast.

 

Anyway, I don't want to turn this into a which media is better thread. There are probably already at least 2-3 of them here. I was just presenting my findings. Do what you will with them. I never made any claims as to lead be superior or a good choice. Just puting my methods out of the table. One may do what they will with them,

[Canadian_Pyro]

Perhaps you should leave the copper tubes on the set of media you use for BP, maintaining the density of lead without the risk of contamination.

 

Lead is far more toxic than copper or zinc, none of them being the greatest things to intake. Brass is also much harder than any lead/antimony/tin alloy, and thus less likely to contaminate your comp, and it does not spark. While it will react with certain chemicals, it works just fine for milling black powder. Recasting is easy if you have access to an oxy/acetylene torch, after all, it is used as a filler metal in brazing. I work with brass nearly every day in my shop, I know the properties well.

 

Maybe we should use glass marbles.

 

To each his own I guess. I enjoy the smell of BP after it is burnt, but when someone launches a shell with lead tainted lift powder, I prefer to step back and let them stand in the cloud of toxic smoke they created.

[Mephistos Minion]

So I am casting some media with this method tommorow, and I have vasoline, but mineral spirits.... Does that just mean mineral turpentine? Or coleman fuel?

[Mumbles]

Essentially it is just another word for Naphtha. Coleman fuel, or turpentine, or other naphthas would work. I think even toluene, and xylene work.

[Mephistos Minion]

Awsome, I have coleman fuel and mineral turps on hand. Just a quick stop by the tip shop tommorow for a ladel and maybe a bigger pot. I dont have any foil tape as it is about $50 a 50m roll. I have blocked tubes with just plain Al foil before so that shouldnt be a problem. I'll take some pics of the process and post them.

[AreteVeteran]

I was wondering has anyone ever cast lead with vaseline and an ice-cube rack? I have one that has instead of the square,waffle pattern, has lots of little cylander holes. It's a special rack for alcoholic beverage ice, and is about 3/4" deep with a 1/2" diameter. with a vaseline coating, it would be perfect for castings.

 

/AV/

[Canadian_Pyro]

As long as it is made of a material that will not melt, it should work fine. Dont use it for making ice you are going to place in your drinks again though.

[Mephistos Minion]

Ok so I had a go at this method of casting lead today. I coildn't find my cemera so I didnt take pics (just as well). All in all it was a failer. I dont have a gas burner so I used a wood fire, the lead just melted, and as soon as I poured it into the tubes it hardened immidaitly. I kept going none the less. When I extracted the bars they were shitty, about as smooth as the moon.

 

Things I will do differently next time:

 

Use a better heat source, such as a propane burner, and leave the melt to heat longer so it is really hot.

 

Pre heat the tubes with a blowtorch so that the lead does not cool immidiatly on contact.

 

Use a better ladel with a more specific pouring spout. (I slopped alot of lead all over the sand and not into the tube.)

[Mumbles]

Mine didn't come out looking all that great either. Some are really shitty because I let them cool too much between additions so there are all these layers. Others have tiny intents from the vaseline droplets, or solvent boiling no doubt. I figure I'll toss them in the mill alone and let it run for a few days and they'll pound themselves into shape. If not, I'll hit them with the torch to melt the surface.

[brainfever]

The crater look is probably from the vaseline boiling off in contact with the molten/soft lead.

These craters and holes in the media will make for a little longer needed milling time, and not as consistent results. Also it's easy for contamination to transfer if you use the same milling media for diffirent compositions

 

I prefer dry casting in short cut tubes, cut with a tube cutter for the crimped ends.

I was looking into treating the inside with HNO3 to make for a rougher surface, to make sure the lead adheres very well.

Copper is inert enough for most compositions, will not spark and is harder then lead. Brass tube is harder, but also more brittle and I don't know how good lead will stick in it.

 

I wish I could afford some gold round stock, that would be ideal

[FrankRizzo]

That'd be some expensive black powder contamination. Who knows, maybe finely divided gold would act as a catalyst

[AdmiralDonSnider]

I´m soon going to cast my own spherical media using those casting forms offered at fishing supplies for pretty cheap. They will give about seven balls at a go, depending on the size of the balls.

 

There are two things I´m interested in:

 

- which alloy should I use? I will use antimony hardened lead, but am not sure how much antimony to add.

 

- Those casting forms are listed by "ball weight", not ball size. They have 15, 22, 44 etc. gram versions. Which one would be best for use in a 4-6" jar? I guess 15 or 22 grams, right?

[PersonGuyDude]

 

 

- Those casting forms are listed by "ball weight", not ball size. They have 15, 22, 44 etc. gram versions. Which one would be best for use in a 4-6" jar? I guess 15 or 22 grams, right?

 

Lead has a very specific weight in ball form. do the old R2 x 3.14 on your desired size , convert to cm cubed, times by the density of lead (11.34g /cm3).