I thought I might share a recent experience with my Shelix planer head. I originally purchased and installed the Shelix head about 4 years ago in a 15" Jet and was happy with the performance, smooth finish and quiet. I rotated the cutters a few months ago, taking them off, blowing the dust away and reinstalling with the nut driver supplied with the head. A couple of months ago I all of a sudden was getting a groove on the planed surface, sort of like a knick in a cutter but this was the opposite of that. I thought a cutter had come loose or maybe a bent screw but after identifying the cutter and trying a different screw still seemed to get the groove so I removed it and continued without issue until this week. I was planning a good bunch of Hickory and started getting several grooves on the surface. I couldn't figure out what was going on. I called Shelix, told them what was going on. After that conversation I removed all the cutters, made sure the head was completely clean and free of burrs where the cutter sets. When reinstalling the cutters I lightly rubbed the bottom on sandpaper to make sure they were clean then reinstalled. While snugging the screw I kept wiggling the cutter until it seated in place on it's own and then torqued to 45 inch pounds. The thing worked like new when back together and after running several bdft of Hickory it was still smooth, as it should be. Maybe this will help save some frustration for someone.