These are our CNC milled idler pulley mounts for the RailCore II series of printers. The mounts are fully compatible with the entire range of RailCore II printers. These aluminum idler pulley mounts are designed to be used with M4 threaded 5mm shoulder bolts (not included). Each mount is labeled to aid in fast assembly of your printer upgrade. They are sold as a set of 2 mounts. One for the rear and one for the front.

Please note that thread milled to a tighter fit than a standard tapped hole. This is to reduce the shifting of the bolt in a loose tolerance hole and to aid to keeping the bolts securely in place.

Please use caution when threading the steel bolts into the aluminum threads as the bolt can easily damage the threads.  We advise starting all steel bolts by hand when inserting them into aluminum threads to insure they are not cross threaded during installation.