I was just thinking how useful it would be to have some lead weights to hold things down as they glued. So, given that I will need lead to make the ballast keel and bricks at some point, I started to think about a supply of lead, and as usual this train of thought got me totally side-tracked. I am nowhere near ready to be making keels, but when eureka moments strike, they need to be given a bit of space.
I have given at least some thought to most aspects of the build already, and one that has been worrying me was the casting of the keel. Casting small weights and the like holds no fear, but the idea of pouring 455kg of lead has been troubling me. But that was before my idea. Like most ideas, it will either prove to be a good one and has therefore been done a million times before, or it will turn out to be the ‘other’ kind. However, to date, I have not come across it elsewhere.
Here is my thinking: instead of finding an enormous crucible of some kind, making a wooden mould and then risking life and limb by trying to pour the molten lead in, why not use a mould that can be heated up, and lob chunks of lead in until it looks about full? The shape of Haiku’s keel is essentially a couple of flat bars, each one about 10′ long, 10″ wide, and 2″ thick, with the lower two edges rounded over. So what, I asked myself, is about this shape and is made of something that I can heat up? The dazzling flash that came to me was… the web of a steel beam. If I can find an I-beam of the right sort of size, I can weld a plate to each end, mount it on its side on some bricks, put some burners underneath, and voilà!