Comment on EXOS2-GT #EXOS2



Comment on the EXOX-2GT mount. I’ve followed this discussion on groups and wanted to throw my 2cent in. Have lots of talent and knowledge on this site. Hope my post will inspire others to learn how to tune the mount and learn what it can do with a little tunning.

My road to Polar Align and two-star alignment and being able to slew to target Saturn and taking 3min long video without adjusting the mount for over an hour. Tracking is great, Same with Jupiter. Also was able to take 30sec long photos of M33 for 1hr. without touching the mount or using a guide scope.

Before tunning, I had several problems right away after initial setup.

1.       Leveling tripod then installing the mount, leg spread, and lose the tripod level if on a slope. I added a bubble Level attached to the bottom of the tripod head for I could level after the mount was attached. Works great. Als see Groups for spreader fix (slip) seem to lock up nice and tight now.

2.       Make sure both altitude adjustment screws are moved together. I didn’t tighten the back screw after polar alignment and lost alignment during an early slew, Head dropped about 2”. Ended Night.

3.       Large cogwheel and a motor cogwheel. Several problems were caused and created when setscrews came loose in either RA or Dec and mount not slewing and doing strange behavior. Took two tries on each to get this right. Must get one setscrew centered on a flat spot of the shaft and tighten down along with 2nd one on another side of cog gear while keeping the alignment of cog gears and clearances. Nice article on this in groups that I followed.

4.       While you have this open this would be a good time to learn how to take the backlash out in the gearing. Follow the how-to article in groups to do this correctly. I half-read the article and it works out fine for the RA. But the Dec not so much. In Dec I didn’t rotate it through 360 deg to find out I had a high point, so when I was testing I got a terrible sound coming from the Dec motor from the binding of the worm gear, though I would burn out the motor before getting it stopped. Regarding Backlash, adjustment follow the direction and due the 360 deg rotation. Seem I’ll have to Live with some backlash in Dec.

5.       When I was buttoning everything back up I ran into a problem when setting the tension on the drive belt in Dec. I would try and tighten it down but would lose it when tightening the screw down. I was able to find a burr on the edge of the screw hole that was causing the problem and removed it with a small diamond half-round file.

After tunning, it runs like a top. Along with the updated firmware for the PMC-Eight this mount is surpassing my expatiation.