david weaver
Thanks for that link, wiley. I recall a decade ago there was some japanning for sale on and off, but each time I contacted someone, I got "I'm not making that any longer, not worth the trouble".

A quart would cover a lot of planes, and it would resist scratches and impact chipping better than paint. The seller says no oven curing - even better. I'm sure it cures faster than my house-made varnish.