I am building a "Coffee Cup Stirling" to Jan Ridders design. Needed to lap the work barrel. Could not find the tin of "fine" lapping compound that I know I have somewhere! In the kitchen I found a tin of "Astonish" a bit dried out. Scraped out half a teaspoonful and mixed with water to a very wet paste. Spread some on a hardwood dowel I had turned to match the bore. Absolutely perfect. Ran lathe in slow and stroked the bore back and forth and ended with an extremely fine finished bore in very little time.
I believe that the water tended to swell the wood slightly giving a nice firm fit that I have not noticed before when using oil based compounds.
JFI Base compound to "Astonish" is "Fine ground white silica flour".
As an aside I have coated the work piston with "Loctite Hysol epoxy putty" mixed with Fine Foliac Graphite flakes, to see if I can make a low friction piston. Now hardened off and I need to machine to fit the bore. No idea if it will work but worth the experiment IMHO
Richard