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AshObservatory

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About AshObservatory

  • Rank
    Nebula

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  • Website URL
    http://mysite.verizon.net/vzeed81b/

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  • Location
    New Jersey, USA
  1. Welcome Aboard Richard, I to can remember seeing Saturn for the first time and saying Holy S---. Needless to say my Orion XT10 used to see Saturn for the first time also picked up this name.
  2. Hello and welcome to SGL. A quick search of the internet and you'll come up with many ideas on building that Dob. May also want to download NEWT
  3. Hi Jeff, and welcome to the site. Where in New England, New Jersey here myself.
  4. Way to go.....Hoping it works as great as it looks....Job well done
  5. Photo of some of the adapters that i use: The Scopestuff EOS to 2" slide comes as one piece and is the lowest in profile that i have seen which might help with any infocus problem. I also add in the TeleVue 2" slide to SCT female adapter when i want to use my Meade 6.3 or 3.3 Focal Reducers.
  6. I have seen all Lunar 100.....now well on my way to imaging all 100. Think last count was either 65 or 66 of the 100. VMA also works very well with Go-To scopes.
  7. New Jersey, about 100 miles south of NYC. Just south of Philadelphia. I was born in NY state, Watkins Glen.
  8. From what i have heard....is a great imaging scope.....ENVY
  9. Hello Joe, welcome to the site. I am also new here. From the east coast myself.
  10. Hi Ben and welcome. New here myself
  11. BTW....Here is a before image. Stock Orion ED80mm
  12. Great image, loads of detail there. Glad you found your guiding problems. This is one reason I got away from guidescope rings and use this setup. Tandem Guidescope Aiming Device
  13. Picked up a 10' piece of 8 1/2" dia 3/8" wall plastic pipe. Dug down about 4' and tapered bottom of hole into a wide bell shape. Installed tie rods (rebar placed in plastic pipe to prevent lifting and twisting movement) and plastic pipe and filled to just below ground level with concrete. Cut pipe to about 4 1/2 ft above ground level and filled with concrete. On top of this will go my G11 to Meade mount adapter on 1/2" stainless steel j-bolts. Total height of pier will be about 5'. No more kneeling (laying) on ground to image.
  14. 1- Added a 3rd axis needle bearing to both RA and Dec axis 2- Cleaned and regreased other two axis needle bearings 3- Lapped and polished worm and gear on both axis, they did have a few rough spots 4- 4- ABEC7 bearings for the worm drive to worm blocks Here is the Losmandy G-11 taken apart and cleaned. All old grease removed from moving parts. I picked up from work a few cans of electric motor bearing degreaser. Anything like gasoline or kerosene would work. Just be aware....Do Not Smoke around solvents !!!!!!!!!!!!! I regreased and reinstalled the main thurst bearing from under the gears as seen here. Here are the bearing blocks with the new ABEC7 bearings restalled. The reason for the replacement of these bearings is they are alot smoother then the orginals. I had to make up a hooked device to pull the old bearings out, came out pretty easily. I reinstalled the gear and worm with blocks. I noticed that the blocks did not sit flat on one side of two of the four blocks. I shimmed using a piece of a business card. I tighten down the block closes to the Oldham gear first. Next pressing blocks together and up into gear tightened the second block. If when turning worm gear by hand is hard, loosen block and adjust. When gear can be turned by hand freely, rotate turn one complete rotationin one direction and then back again. I found that my gears were not perfectly round. I hit a spot of about 30 degrees that the worm gear would bind. So I had to loosen the worm block again and adjust for this tightness. Which now made the backlash of the other 330 degrees of the gear worse. This is when I decided to lap the worm and gear. THE PURPOSE OF LAPPING THE WORM AND GEAR IS TO REMOVE ANY IMPERFECTIONS BETWEEN THE TWO AND TO GET A BETTER GEAR MESHING WITH MINIMAL BACKLASH. Any hit spots on the gear or worm will be ground down . And will be polished with the finer grits of lap. Polishing will give alot less friction between the two. Photo below shows the lapping being down. I started with a 1200 grit (which is pretty fine to start with) as i didn't want to take off to much. I put a 3/16" drill bit in my varible speed drill with the point in. Leaving the 3/16" shaft to attach to the Oldham coupler. Putting a tab of lapping compound ( mixture of powder and 30W motor oil) on the worm gear and then also around the gear it self. Using the lowest speed on the drill i rotate one complete rotation to make sure it would not bind. Then changed directions. As the lapping compound was used up more is applied just to the worm gear. This procedure was continue for 20 mins. Everything felt smooth when rotated by hand again. I then moved the worm block a little closer. Again rotate by hand before using drill to make sure it doesn't bind in either direction. It should be a tighter fit. I lapped again for 20 mins using 1200 grit changing directions every couple of mins. I could tell from the drill continuing to rotate when turned off to change direction that the mess was getting wider. Time to move the worm block in again. Continued lapping for another 20 mins with the 1200 grit. When completed, I took the gear and worm gear off and cleaned. Removing all lapping compound. Then reinstalled and checked backlash all the way around the gear. Everything was fine. No visible backlash like before and no tight spots. You can see the business card spacer used on the right worm block. Then proceded with the same process as above with all the grits ( 1600, 2000, 4000,6000and 8000). Cleaning between grit changes. Total time spend on both the RA and DEC assemblies was about 10 hours. There is now no shaft movement (as before) all the way around the gear. My backlash is basically gone. Photo of the finally polishing with 8000 grit lap compound. Worm and gear after final polsihing and cleaned. Ready to be put back and regreased.When greased, I also used the drill (setup like in lapping) to spread the grease around and polish even more. When everything was reassemblied, turn worm by hand ( using the Oldham coupler) a complete rotation in both direction for binding. You want to be able to turn by hand and no or minimal backlash. When both the RA and Dec shafts back on I also put the wavy washer on the outside of the spacer block instead of on the inside. Doing this does not affect tightening but does make a smaller gap for any dirt to enter thurst bearing. Also while i had apart, i finally got my polar scope to freely rotate with the clutch tightened down. Before I always had to loosen to rotate polar scope. Final photo is worm gear and gear after final polishing and ready to be put back on. It is my understanding that Astro Physics laps all their worms and gears before being shipped. I can't argue with the quality of AP mounts. I found this procedure fun and easy to do. Granted it does take some time to do but hopefully all well worth it. I have not had the mount back out yet to try. PS....No left over parts Some additional closeup images:
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