Wood will burn. Just find some damp soil, like in a flower bed, remove sticks, etc. and use a finger to draw a groove in the dirt Pack the dirt down with a wet finger, to give the ingot a smooth cast. Pour the lead in the dirt grooves to make whatever length stick ingots you want to carry on a trail walk.If you have clay soil around you, it also works well, just allow the dirt to dry and absorb any water before pouring lead into the grooves. Let the sticks set up and cool- they will cool fairly quickly if not made too thick- and then wash the dirt off of them with your garden hose.
I did this with my father when we were kids, first melting scrape lead to clean it, and put in a more storable form. We didn't have a lot of choices for molds- he had one small hubcap looking stainless steel fitting that cast round ingots, but they were slow to cool, and so dad walked over to the flower bed and drew a line with his finger. Then he had us get a bowl of water to dampen our fingers, and smooth the bottom and sides of the grooves. The bed was in full sunlight so by the time we had more lead melted the grooves were ready for use.
If you want to make grooves in a pine 2X 4, or something similar, You can protect the wood from burning by soaking the wood in motor oil. The oil will burn or smolder, but the wood will only char at the edges of the grooves.
It would be safer, of course, to get some sand, mix it with old motor oil, and use it for your casting molds. This is generally how sand castings are still made. If you have a piece of 1/2 inch diameter dowel rod, you can use that to make the grooves for casting, Put oil on the dowel to act as a release agent, so sand won't stick to it.
Thanks!
