Free Form AIR™ Sculpting Epoxy is recommended by World Champion Tyler Erickson. It smooths out easier than other sculpting epoxies.  It is very easy to sand and you can carve fish scales after it dries.  This is a low-odor, low shrinkage putty that is unique, inexpensive and easy to use. Free Form™AIR is mixed by hand with a 1A:1B by volume mix ratio. It offers a long working time and cures overnight at room temperature to a hard, rigid epoxy that is very strong. Cured Free Form™AIR is so lightweight, it will float in water. Besides being sanded after drying, it can be shaped, and drilled. It will readily accept any paint.
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov.