Thank you very much. I had luck, because i had to made 4 devices again/new. its hard to cast copper in resin because the air is sticking on the copper really microscopic small. when the resin begins to dry, the air stucks on the copper wires. i think its "micro-rust". resin when it drys, begins to heat up. the small air bubbles getting bigger because of the heat and breaking the drying resin into 2 pieces. Thank you very much for looking and comment.