Firebox weight patterns

Little eight wheelers like 622 are mostly air. So, I need to fill every nook and cranny with weight. The firebox looks like a good place for weight, but it is unfortunately rather full of gearbox and other mechanical or electrical gubbins. The forward end has a little space, and so, I carved these two patterns out of wax, and The Boy is going to help me cast them in lead.

The wax is just paraffin, and Michael’s sold me a lifetime’s supply for about three dollars. However, I had to learn how to carve it. The key is to start with a block that is big enough to not admit any fractures; it should look smooth and homogeneous. Then, use a knife to take shallow cuts, always taking less off than is left in the shape; that way, the fractures will appear in the removed curl, rather than in the pattern. I made two of the right pattern and four of the left before I managed to properly learn this!