Day: August 9, 2015

Lazy Susan Mod for the Orion XT10 Azimuth Motions

     All I have to say is why didn’t I do this YEARS ago! I just gave a 6 year scope that hasn’t really been used in say well over 4 years except for outreach and occasionally at home. A long time ago I added from Tony C. at Astronomy-Shopper (LINK) his Scope Grips.  They were a MAJOR improvement in the altitude system for my Orion XT10.  I could loosen or tighten the knobs to increase or decrease tension depending on my eyepiece. To be honest, I found a position for the eyepieces I used and left it there for my observing session. I may have to make one adjustment just to tighten later that night. I highly recommend them if you have a stock Orion XT dob. I also got Tony’s Scope Totes (FYI, I don’t get anything from Tony I am just sharing info) which you can see both in my video and at this LINK.  There are cheaper alternatives like the Strap Handle LINK  or over at Home Depot (also Lowes) is the Velcro Hand Strap Handle LINK.  I like that the Astronomy Shoppe Scope Totes fit my OTA and they make it so much easier to life. I find that after a year of losing 80lbs and working out four times a week, that the 10″ is not heavy to lift at all. It is just awkward and the Scope Totes make it easier to life.  

     Now the only real issue I have never liked on my Orion XT10 are the azimuth motions. I didn’t mind the stiction I guess when I didn’t know any better, but my 14″, 17.5″ and 24″ have made me realize and adore buttery smooth motions. I have read before about adding a Lazy Susan bearing to the XT10 LINK and I finally after an evening of outreach about 2 weeks ago, decided to give it a try. The worst thing that could happen was I had to remove the Lazy Susan, have four holes in the bottom of the base board and return to the current method.

     Well, I ordered a 12″ Lazy Susan bearing since I could not find one locally and it arrived earlier this week. I went to Lowes today and got both some #8 screws in the 1/2″ size to mount the Lazy Susan on to my base board.  I had extra carpet so I cut about 1″x1″ strips and flayed off any carpet that might want to come off (so they don’t go into the bearings and mess this up) and used black electrical tape to secure them. I am sure I will have to adjust that later but that is fine.

     To get started I took the base apart, something I have done quite often trying to improve the motions in azimuth and then took the bottom base (some put the Lazy Susan coming down on top of the base; I went this way as I was thinking that if I had it come down and facing down, it might be easier to get dirt into it but on re-thinking it, it shouldn’t. I did it this way as it made sense to me as if I was actually installing a Lazy Susan in my wife’s cabinets.  Anyway I WISH, I really WISH I had filmed me measuring out my two lines, each intersecting the middle of the hole in the board. With those lines drawn, I measured the inside diameter of the Lazy Susan, the open part, and then measured using a caliber and a compass the exact location where the Lazy Susan should be. I then used a punch to make a slight hole in the center of where the Lazy Susan would attach, removed the Lazy Susan to my bench to protect it from dust and drilled, using a bit smaller then the diameter of the screws I was using (#8 1/2 inch) to start the screw.  I then changed the bit out, put in my bit into the drill, laid the Lazy Susan back on the base, lined it up perfectly and screwed down the screws securing the Lazy Susan!  My next step was to put the carpet down to act as breaks, (I put one down behind each teflon pad, one isn’t in place yet in the picture) which they do nicely and as you can see in the two pictures.

   

     I now reassembled the base by putting the bolt back in and securing it, and then putting some a smooth nylon washer down on top of the bolt (where it would stick through in these images) and then I put 5 Milk Jug Washers here to further help both the motions and to break it. I did leave the Teflon pads on as when I got done the pads were still well below the base.  Last I secured a washer down and then another nylon washer and Milk Jug Washer (My nylon washer replaced his rubber washer in the link I posted above) and then secure the bolt down.  
     When done, I wasn’t sure how much I was going to have to play with as I assumed it would take assemble and reassemble several times to get the stiction and motions right where I wanted them. I keep the XT10 in a bag my wife gave to me one Christmas to store it, and pulled out the tube.  I put the modified base out in the grass in my front yards because I had a good 10 mph wind/breeze going with gusts to around 14 to 15 mph, and I wanted to test it out. After putting the OTA on the modified base I moved it and BOOM! Perfect!!!!! I let the scope take the breeze from the southwest full across the tube to see if it would move, and it didn’t.  
     I next moved it back to the garage and decided I better film this and I did do.  I have to say that I am REALLY excited about this 10″.  Good mirror in it now, good motions, it is my go to for outreach (allowing me to keep the 14″ and 17.5″ for observing) and to let young people learn on it. I agree that I will probably have to exchange the Lazy Susan every couple of years but at $12 to $20 shipped, not an issue. I also now have a decision to do in the backyard. Refractor which I love or 10″ reflector? I think the old XT10 has a new life and all from a simple mod that honestly took about 1 hour to do.  If you want to improve your motions look over the links and my notes, shoot me a line and if your local, I will be happy to help you (but it is your decision so don’t get mad at me if something doesn’t work right!).  You will see in the video I have the 17″ set up in the garage as I had to exchange out the Milk Jug Washers on the secondary and do a few more mods (always a work in progress and I have learned to really like to tinker with my scopes).  Here is the video I did in my garage after setting back in there. Again, easy mod to do, and I’ll keep you posted if for some reason it goes south but I don’t see any reason for that to happen.