The black epoxy is a strong adhesive just like other epoxy resins. Cleaning it up after usage could be a hassle if you are not proactive. To clean the black epoxy, you have to remove the excess one from the surface with a sharp object, you will then sand it out once it is dry. However, make sure the gloves are wet when you want to sand epoxy. You can then use a solvent such as acetone to remove the residual. If possible, you should also clean the area with water.