Celestron 8 Focus Motor
The Rajiva MCU Update supports powered focusing from either a PC or from the hand controller. As I had already built the circuitry to handle this (see my page on this; it was time to hang a motor from the scope. I used the leftover Conrad motor and the original Synta gearbox from the Conrad motor upgrade and built a suitable bracket from the bottom of an old VCR. It's nice galvanized steel; a bit flimsy and I had to make some side braces, but it works well. If you use 1/2 decent material you shouldn't need the braces.

A drawing of the bracket is shown below (drawn for Synta gearboxes), along with an image of the mounted motor. The steps in this fabrication were:
  1. Print the drawing out 1:1 scale. It is at 100dpi so it's fairly simple.
  2. Glue the image using water soluable glue to your material
  3. Use a band-saw to cut out the image, then drill/ream the holes the correct size
  4. The line below the motor mounting holes is where it has to be bent. Put the work in a vise and bend it down then tap it as tight as you can with a hammer. A few thousanths out won't hurt.
  5. If you are using 'flimsy' material like the plate I used, use a pair of pliers to put a small bend in the edges of the long sides of the bracket to add stiffness
  6. Obtain some suitable screws to mount the motor plate on the OTA in the unused mounting holes from the fork mount.
  7. You're done

Tools used:
  • Band saw
  • Hack saw
  • File (to smooth the edges etc.)
  • Drill press
  • Hole cutting bit for the drill press (I don't know what they're called but they make round holes)
  • Table vise
  • Hammer
  • Pliers

You'll need to obtain or make a suitable pulley for the shaft of whatever motor you are using.

The motor will drive my focus wheel extension using a decent quality elastic band. This will provide enough 'oomph' to turn the focuser (it's very smooth) but will be easily removable if I dont' need the powered focus.






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