I finally started putting together the 8″ f/4 dobsonian that I’ve been talking about building for a couple years now. One of our neighbors helped me cut the sonotube into two sections, one for the primary mirror cell and one for the secondary cage. Then I drilled and cut the holes for the mirror cell, spider, and focuser. They’ve all been temporarily mounted so that I can test the optics and get the final positions for the secondary cage. I’m using an open tube design that will be using six aluminum rails to support the two sections. I got the idea from http://www.usno.navy.mil/8inchdob.html. Next weekend I’ll finish putting together the OTA, build the base, and collimate the entire system.