ok heres all i can say about this,,,if u make a metal fence frame,,,then make one outter layer across the metal frame with whats called fiberglass matting,,,let that dry,,when u mix the resin u add a hardner to the mix that causes a chemical reaction and makes the resin harden,,,u soak the fiberglass matting in the resin then hold it up in the air let alot of it drip off then lay it on the metal frame,,,,it will harden and dry pretty fast,,,once u get the outter shell done then turn it over and use a paint brush,,,just mix some more resin (which is the wet liquid stuff) and use a paint brush and brush it on smooth on the inside of the cave ure making,,it will harden fast also,,resin does not have fiberglass in it so it will not effect the snakes at all,,i can understand if the fiberglass matting got on the snakes,,that would be bad,,,but if u keep putting resin on and make it smooth like glass then u wont ever see fiberglass on or around the snakes,,once that dries flip it back over and brush on the resin on the other side,,just like the underside,,,then once its dry paint it how u want it,,,will look awsome,,ill do it just to show everyone how its done,,ive made alot of fiberglass car parts so im sure i can do a cave,,lol