Sunday, May 14, 2006

Smelting

I was reading a thread over on the Cast Boolits forum talking about smelting lead.

Cast bullet shooters get their lead from a variety of sources, including roofing fixtures, medical waste, telecommunication waste, and plumbing waste. We are recylers of the highest order. Old sheathing from an x-ray room remodel? Throw it in the pot. Cable sheathing found on the side of the road? It goes in the pot. Hurricane damaged roof flashing? Oh, yeah, it goes in the pot too. By far, the biggest source of lead bullet material is wheelweights. Those little clips they use to balance the wheels on your car. Wheelweights are made of lead, with some tin and antimony. They are hard lead, and great for making bullets. They are also very inexpensive, even free when a dedicated scrounger is on the hunt.

One well-known bullet caster once said "If it looks plumbous, I'm apt to make bullets with it."

Turning scrap lead into something useful requires melting it. Often in large quantities. This is easily done on a propane burner, your turkey fryer will work just fine. You can also use a Coleman stove, but you have to be aware that you are melting metal at very high temperatures. Safety is absolutely required. One little slip and you will enter the ranks of the severely burned.

In my second or third article for The Frugal Outdoosman, I covered bullet making safety. The same rules apply, so let's review them.
WARNING Casting bullets is dangerous. In addition to the dangers inherent in working with molten metal, lead is known to cause birth defects and cancer. Work outside or exhaust fumes to the outside. Wear safety goggles or glasses. Wash your hands before eating, drinking or smoking. Never allow liquids near casting area.
Never allow liquids near the casting area.

When we smelt scrap lead, those same rules apply. Get outside. Wear protective clothing, including eyewear. A pair of safety glasses costs about $5.00 down at the hardware store. What are your eyes worth? While you're there, pick up some gloves. Stand upwind of the fumes. Gather all your materials and equipment and keep the kids away. No playing, no alcohol while smelting. Someone could get hurt. Badly.

What we want to do is melt scrap lead and turn it into something useful. We need molds to pour the molten lead into. I use a variety of ingot molds. I have three of them depending on the type lead I am smelting. Pure soft lead goes into a square ingot mold. Wheelweights go into a discarded cornbread stick mold. Alloy goes into a specialty mold I picked up at a garage sale.

Water is your enemy. Lead melts at something around 620 degrees Farenheit. Water boils at 212 degrees. When water is introduced to molten lead it flashes to steam with explosive force and expands dramatically. That instant steam rises. One drop of water in a pot of metal will empty most of the pot of molten lead in a violent splash. Let's look at a picture taken at my house, in November 2004. You can click on it to view the full size photo.



In this photo, I had my smelting equipment set up on my driveway and was melting wheelweights for bullets. I had already melted some pure lead flashing and wanted to render the wheelweights to make some alloy. I filled the pot with raw wheelweights and let them melt, skimming the steel clips.

Unbeknownst to me, those wheelweights had recently been moistened inadvertently in a rainstorm. When I initially loaded the pot, everything was cool and as the scrap heated, the moisture evaporated off the metal. When I skimmed the steel clips, I decided to add some more raw wheelweights. When I dropped the first one in the pot, it exploded. Evidently, the wheelweight I dropped in the pot had some moisture on it, probably under the clip. As the wheelweight entered the molten metal, it fell toward the bottom of the pot and the moisture flashed to steam. The pot erupted, scattering molten lead across my driveway. I've included a measuring tape in the photo for scale. Most of the splash was confined to a three foot area directly adjacent to the pot. Later, while cleaning up, I found splashed droplets of lead as far as six feet from the pot. Any one of those small missiles could have caused excruciating pain and disfiguring injury. At the time of the accident, I was wearing safety glasses, a long sleeved flannel shirt and a baseball cap. I was not injured, but only by the Grace of God. My hand was within inches of the pot, as I was dropping metal into it.

Casting bullets is a wonderful way to turn scrap into useful material. It is a hobby that has given me years of enjoyment, relaxation, and education. Primitive metallurgy takes us back to the dawn of the Industrial Revolution and makes us more self-reliant. It is a magnificent hobby. Practice it, learn, explore, but be careful.

Update** A reader found an upwind/downwind error in the article. Good Catch! I fixed it.

3 comments:

Redneckdan said...

Don't you mean "up wind" of the pot?

Pawpaw said...

Yeah, Dan. Stand upwind of the pot. Good catch!

Anonymous said...

Reminds me of my first time melting lead and casting bullets, 30 years ago.
I was using an electric pot, on a desk, indoors. (wait, it gets worse) I was sitting directly in front of the pot, finished my work and decided let the remaining lead cool in the pot for the next time. I reached under the desk, grabbed the wire and jerked the plug out of the wall...I also jerked the pot off the desk toward me. My next coherent thought found me standing three feet back from the desk watching a 1 foot puddle of lead eat through the carpeting and wondering why it wasn't in my lap. I'm guessing: guardian angels. Still gives me goosebumps.

Flintlock Tom