127mm f/9.4 Cradle Rings Construction - Cradle Rings - Knurled Knobs - Top
 

Top-view of one of the Knurl Knob used to lock the telescope into the Cradle Rings... (Click for enlarged view)

 
To secure the two halves of the cradle rings around the OTA's main tube, I purchased two stainless steel knurled knobs from McMaster-CarrŪ. Not cheap at all, but they will last a long, long time. The top has a brushed finish and crosscut sides. In conjunction with a brass threaded rod, and dowel nut, they will make up the cradle ring main tube locking system.