#woodworking
oh, and as long as the oven was hot, I tried a tiny experiment in the chemical "burning" of patterns into wood.

I have a few scrounged squares of pale-colored, very thin plywood of the sort that's often used to make bits of blank wood for crafting projects. I hoped to use these squares for experiments in chemical woodburning. The idea is: apply some sort of chemical treatment, usually with the aid of heat (as from a heat-gun) which causes unusual darkening or scorching of the wood. Fumigating wood with ammonia, for example, will darken its color and even "ebonize" the wood (i.e. turn it almost black) with suffiicient exposure.

The usually cited method for achieving chemical wordburning employs ammonium chloride, sal ammoniac, dissolved in water and thickened into a paste. I have some sal ammoniac on hand, but I was keen on trying another idea I picked up from some articles in the technical literature: treating light-colored woods with citric acid solution and then heat treatment turned the wood a rich red-brown color.

It does! I can verify that, anyway. Unfortunately the citric acid paste I made (1 tbsp food-grade citric acid in 1/3 cup water + 2 tsp corn starch, heated and stirred in a double-boiler until the starch was thoroughly gelatinized) tended to bleed into the wood around the edges of the stencil, so when I baked a piece of wood with the citric acid paste applied, I got a rather ugly irregular red-brown blotch. I wish to try again, but taking care to apply a much thinner layer of the paste.