I have 2 Bishops and they both do the same. I can say that the slides are not to tight (Checked them) in fact they all move very freely with a little slop. I've removed the stay up springs. Spent Close to $400.00 on new Eikon ems 400, New clip cord, and foot switch. Guess what??? Still gets warm/hot. Just depends on how long you work with them. Mine get warm/hot within 1 hour running on 9-9.5 volts. I personally know 3 other people (One in my shop) that have them with the same issue.... (Just my opinion) Neo tat Vivace is a much better machine and cost less. I can run those babies on 12 volts for hours with no heat issues...