I am figuring out how to make my own weighted pencils. I took a pencil and wrapped tape around it (the way you do a ring that is too big), then I put a bolt on it and it fits snugly. I had taken pencils to the hardware store and found bolts that fit close but still a little loose, so the tape was perfect. First I tried super glue but it wasn't quite enough. Tape worked better. 🙂 But i am not sure the best placement of the nut on the pencil, so I may do some experiments with that, and also try putting more than one nut on, etc.