I optimized my jig for attaching the side and center bearings to the mirrorbox of a Mel Bartels type trilateral dob. Makes it a very simple task now. See http://home.wanadoo.nl/jhm.vangastel/Astronomy/tridob/tridob.htm Jan http://home.wanadoo.nl/jhm.vangastel/Astronomy/ _______________________________________________ ATM mailing list http://www.atmlist.net/