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Don1357
01-24-2021, 03:47 PM
I imagine a logical extension to casting boolits is to look at casting fishing weights so I'm hoping to get some pointers from those that cast the bigger stuff, 3+ pounds.

I have been working on the equipment. The pot is a mild failure. I wanted a bottom pour, got a hold of a 6" ID 8 1/2" tall 1/4" thick pipe. I modified and installed a Lee bottom pour rod and hole, enlarged it a bit. The fail is two fold; the skinny design doesn't lend itself to soak up heat as well as a wider design, it takes a whole lot more heat than my unassuming cast iron pot. The other problem is that it tends to drip, which is not such a big deal. I may need to engineer a better burner for it.

The real "I'm going to hurt myself" fail was the burner. I got a jet burner which gets hot enough, and I installed a chute for the molten lead to travel into the casting area. Fail number one: The chute gets red hot; as in hot enough to vaporize lead... Fail number two: I built it with square tubing, and many other places that get close to red hot are also prone to get the occasional lead splash, which also looks like it could vaporize lead...

I'm putting the bottom pour pot aside for a while, I'm throwing away the ill conceived burner setup, and i'm going to work on a better burner. Before I do that, for those casting big fishing weights in the 3 to 15 pound range, how do you do it?

ReloaderFred
01-24-2021, 04:03 PM
I have a close friend who used to make those big cannon ball sinkers for fishermen. He had a casting blow up on him, and he nearly lost his eyes to it. Air got trapped inside the mold while he was pouring and the super heated air caused an explosion and covered his head and face in molten lead. I would caution you to do some research before attempting this, as it's not like casting bullets.

The next time I talk to him, I'll ask him how he finally worked it out. He's going through some pretty serious cancer treatments right now, but I'll see what he has to say on the subject.

Hope this helps.

Fred

Don1357
01-24-2021, 04:12 PM
I have cast 12-pounders myself, very inefficiently and somewhat ugly. The secret is very hot molten lead and the reason I have avoided your friend's fate is because of my impatience to wait for it to get it that hot :}

Right now I'm dumbing down my process. I'm going to focus on the burner top and a larger cast iron pot. I'll go back to my big ladle that can carry about 3 1/2", and the biggest upgrade is going to be doing some weight lifting to make the ladle with the long handle feels lighter :D

Eventually I would like to work on efficiencies in case I want to work on this as a paying hobby during retirement.

Mk42gunner
01-24-2021, 08:15 PM
The biggest I've done is 8 and 10 ounce bank sinkers in a Do-it mold. I used both a Lee 4-20 and just a dipper from my smelting pot.

My biggest issue was venting the mold, the original fill hole just wasn't enough to let the air out. I ended up enlarging the fill hole to roughly 3/8" before I got satisfactory results. There is no sprue cutter on these molds, but I found if you didn't wait too long, I could twist the sprue off; either with gloved hands or a pair of pliers.

Since these were destined to get lost anyway; looks don't matter, and it is a decent way to get rid of nasty alloy that doesn't make good boolits. It does hurt loosing 1/2 a pound or more of lead every time the line breaks though.

Robert

MrWolf
01-25-2021, 08:01 AM
Just a lil early morning thinking but what if you just made two halves and bolted them together? Don't need to look pretty and gonna loose them anyway? Pouring a bowl type mold has to be easier and safer. Good luck
Ron

gbrown
01-25-2021, 10:43 AM
Why not make a casting using a box with casting mix? I use a type of cat litter and sandbox sand. Dad made ingots of 10 + lbs using this method. He made a wooden box about 18" X 18", filled it with casting mix slightly moistened, press his desired shape in it and let it dry. Come back and smelt the lead and pour it in. For beach weights, he used an old metal drinking cup, pressed it in and took old copper wire, 2 pieces about 5 inches long, bent in the middle slightly, layer them across the mold at right angles, like a + sign, and pour. Ended up with puck like weight (8oz+) with copper arms to dig in the sand. Cast it, let out more line, and the current wouldn't bother you on surf fishing trips. Watch the video on Corporalscorner on YouTube, How to make a bronze skillet. Interesting.

gbrown
01-25-2021, 11:13 AM
I looked through my notes, and the mix is called green sand. There is a tutorial on it, Making Green Sand. That's what I used. I got my clay from a cheap bag of cat litter. Found it by reading ingredients of the bags. Bentonite clay. I've made casts of several small objects using this method. Its how they originally made cast iron utensils pre 1850. I have a cast iron skillet with a sprue mark on it made in this manner.

Don1357
01-29-2021, 04:43 AM
I already have molds for 10~12 downriggers, doing them with sand casting or two halves would actually be harder than sorting out the use of the molds with finesse. Heck for the bullet jigs the molds (which I also have) hold in place the eyelet and the hook in the exact right place, any other method would be a step in the wrong direction.

The problem right now is the technique and equipment to keep a good 30+ pounds of lead melted and pouring 10 pounds at a time.

Mk42gunner
01-29-2021, 10:11 PM
The problem right now is the technique and equipment to keep a good 30+ pounds of lead melted and pouring 10 pounds at a time.

Get a bigger pot. Otherwise I foresee some horrendous wait times for lead to melt. I'm not sure my smelting pot has enough capacity for what you want to do, and it will hold some where around 90-100 pounds.

Robert

mrmachinist
01-29-2021, 10:41 PM
At work we will cast lead impression blocks for down hole companies on occasion. Sometimes it’s close to 100lbs of lead depending on the size.

We have a steel bucket (roughly 3 gallons) made from pipe with some round pipe handles off the side we put on some jack stands. Welded a pour spout on one side and a lifting eye on the bottom on the opposite side and we use a jib crane to make the pour. Propylene burner under the pot.

Works great. A scaled down version would work great for your application.


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