Use heavy negatives on the dip machine for triceps. I absolutely love doing these. It's an effective, safe way to overload your triceps with heavy loads.
Have someone help you do the concentric portion of the lift. Then do the eccentric or negative portion by yourself. Take a few seconds to lower the weight.
James Chan is into machine gunning, shot guns, and cross wiring. If we didn't know better, we'd think he was one of those militia guys holed up in some shack in Montana, swearing never to be taken alive.