The project for today was to help brother Bob pour a new one-piece inside ballast – approximately 600 lbs. – for the new Haven 12.5 sailboat that he bought in August. The boat came with an already constructed mold for the keel. All we had to do was heat up the lead to about 600 degrees Fahrenheit and pour the lead into the mold.
Bob had arranged everything before I got to his house. The melting crucible was balanced on cement blocks with a large propane burner beneath it. Bob had loaded about two thirds of the lead into the crucible and had lit the burner before I got there. Our friend Russ Ericson was also helping out.
Bob had put a threaded fitting in the bottom of the crucible so that the fitting fit flush with the inside bottom and threads extended below the fitting. On to the fitting Bob had fitted a two-inch pipe that ran about four feet to an elbow that would direct the molten lead to pour into the mold. And there was a burner under the pipe.
A threaded pipe also was threaded into the inside of the bottom fitting. This pipe had several holes drilled in the threads. When the pipe was screwed down, the holes were inside the fitting. As the pipe was unscrewed, the holes opened to allow the molten lead to flow down the pipe and into the mold.
After two-and-a-half hours, the lead – all 600 lbs. of it – was melted. We had the burner under the pipe burning hot and had added a pot full of charcoal (also burning) under the pipe between the crucible and the mold. We had also fired up a hand-held propane torch with which we were heating the last eight or nine inches of pipe and the elbow.
With the lead fully molten and the pipe at about 300 degrees, Bob opened the pipe with the holes. Lead began to flow into the mold. Bob opened the pipe completely and the molten lead poured down the pipe and into the mold. When all of the molten lead was in the mold, we turned off the burners and watched as lead bubbled in the mold for about fifteen minutes. The lead had stopped bubbling and we went to have a cup of coffee.
Bob will leave the lead and mold alone for a couple days to fully harden.
And, next spring, Bob will take the Haven 12.5 to the family cabin at Priest Lake, Idaho.
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