I have watched this thread develop and have not joined in because I dont do stamping.
However as one who likes to keep things simple, I can't help wondering why anyone would want to mix their own black epoxy, when single jars of black efcolour enamel are readily available from Cookson, or Metal Clay.
It is fixed in a kitchen oven, for three minutes at 150 degrees C, or by using their inexpensive tealight heater. Being a powder, it should be easier to control too.
http://www.metalclay.co.uk/efcolor-c...mel-stove-set/ Dennis.