When making something to a specific size, you often have to follow a pattern. But a normal paper pattern will catch on fire. So you need a slate.
Any piece of rusty sheet metal 10-12″ a side will work for most patterns. Put chalk dust on the back of your pattern, then trace the pattern onto the slate with a blunt pencil. The rust acts as a dark background for the light chalk.
Note that I said rusty, so no aluminum (won’t rust), stainless (shouldn’t rust), or galvanized (will poison you if it gets too hot).
Now like a bone head I forgot to wet my fresh metal and now I don’t have time before class. So I’m using gun blue instead. The metal is already clean, so I just need to apply it.
Make sure you dry and oil it afterwards so it doesn’t rust… um well I guess that doesn’t matter in this case.
Next I docked the sharp corners using my trusty old harbor freight shear.
It’s a bit floppy, so I used brake to bend up one edge. (Could do two or even all four, but even one helps a lot.)
Then I closed the seam with a small anvil and brass mallet. I want it nice and tight so my metal will lie flat on the slate.
The corners still bug me, so belt sander time. (Files would work too.)
Cool. Now I just need to blue it again because I scratched it all up with the anvil. Next time, bluing goes last.