The ATM session on 3/3 was the most heavily one attended yet. Charlie, Jay, Jeff, Josh, Troy, Levi and Hayden all attended. Things got rolling with us testing Jeff's 10" mirror from his Orion dob. We tested it to be just better than 1/4 wave. There was a central hill, but it is hidden by the secondary. The surface looked reasonably smooth and there was no clear evidence of excessive zoniness. Jeff's plans are to eventually rework the mirror. At that time, and after the coatings are stripped off, we'll have a better look at the overall smoothness and polish. He then will decide to just touch up the figure or perhaps more fully polish it. After that test, Jeff showed up how to properly use the Catseye collimation tools. This was impressive to me. It certainly looks to be a very thorough way to collimate. Thanks Jeff for sharing! Jay brought plans to share for the best observing chair I have seen yet. He has posted the plans for that chair on this forum under the ATM heading. He plans to start building the chair during the next session, maybe before. Josh started polishing his 4" project. His 4" pitch lap was previously used on an 8" mirror so we first pressed the lap into contact with the 4" mirror. This took a fair amount of time since the lap originally had a ROC of 96" and the 4" mirror has a ROC of 32 inches. A couple of hot presses and it was making fairly good contact expect for the very center. Since mirrors almost always polish from the center out, I encouraged him to go ahead and start polishing and eventually the lap would fully conform and the center would then catch up. After a 15 minute stint, we checked it and sure enough, the center was not shiny, but from about 1.5 inches out it was. A Ronchi test showed that the mirror is spherical. Fortified by this good news, Josh was rededicated and started polishing again with Jeff and I taking a turn. After another hour or so, the center was now shiny and the Ronchi test showed a very nicely spherical mirror with no TDE. Good job, Josh on your first mirror! He just has more polishing ahead and then figuring. Troy and sons Levi and Hayden came by to start work on the mechanical part of their 8" dobsonian. We got the tube-cradle boards cut and partially glued and reinforced. Next step is to make the mirror cell and the rocker box. Fun stuff! Keep pushing glass! Mat