I have experimented with various encaustic recipes, some worked, some didn't. Now I stick with the traditional recipe of beeswax and damar crystals. Note that this *very different* from damar *varnish* which contains solvents. Damar varnish should not be used in encaustics as it is highly flammable and can give off toxic fumes when heated! I have also had good luck with a mixture of beeswax and a colorless synthetic hardening wax (lustre wax from www.fineartstore.com) in about a 12:1 ratio of beeswax:synthetic.
Making a note here.