I noticed on a few other discussions of the problems with the 1 1/8 inch threaded inserts not meshing well with the lathe spindles. The one I recently purchased went together extremely well with the chuck and the lathe spindle. That being said what I would like to know from other users is how long do those fiber washers last with the grub screws and are they absolutely necessary for operations. I contacted teknatool about getting some replacements and they gladly sent me 4 more along with extra set screws at no charge but I was wondering how long those would last because they seem to get mashed flat at each use.