Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Alcohol dilution?  Absolutely.  Ten percent H2O sounds like a good
starting point.  Experiment! 

As to grain alcohol....Amen on that, two ways.  It burns very
cleanly and if you have extra it makes a nifty cocktail.  Just
don't try to drink it straight.  I use it to power my PM Research
Solar 7 Stirling engine and it NEVER leaves any residue on the
glass tube.  If it did, it would show.

Happy steaming,
Wayne