The best way to clean pipes is to boil some water and then put the water and your pipe together in a cup or something. Shake the cup or pipe every once and a while so the resin breaks free and falls to the bottom of the cup. After most of it is out of the pipe you can use a coffee filter to strain out the water and leave the resin. Roll the resin into a ball and let it dry then you can just smoke it in your pipe.