When sandcarving, we recommend that you use tapeless inserts in conjunction with your choice of putty, which allows you to make molds of your most popular pieces so that you no longer have to mask them off. Masking off the substrate you are getting ready to blast can take a good chunk of the total time it takes to prep the piece; this system saves our etchers many hours of prep work.
-Wes Barton, IKONICS Imaging