My amateur telescope making page

The "Deep Space Scope" Design

Home | Astronomy | DS-3 | Details, current issues and future enhancements

Final assembly

• One of the final things to do is to attach the bearings. Place them against the side of the mirror box where they should go, set up the scope, and figure out if it balances. I used 1 1/2" screws for this attachment.  If it is not correct, move the bearings. Try it with the lightest setup you will use (no eyepiece) and the heaviest eyepiece that you have.  Be sure to do this with the finder and baffling in place.
  
• Place a series of plastic washers around the center nylon bolt going through the rocker box and ground board.  These are generally cut out of milk jugs.  You want most, but not all, of the telescopes weight to sit on these washers, creating a bearing with a small moment arm.  This makes the telescope turn very easily in the azimuth direction.
  
• You may need to put some Teflon spray on the bearings.  WD-40 also seems to work.
  
• You may want to cut down the bearings, by removing portions of the arc that are never used. This is done by pointing the scope straight up,  then another 10 degrees, and marking where the Teflon touches the primary bearings. Then, place the scope horizontal, and once again mark where the Teflon bearings touch. Cut the excess material off of the bearings.  Round the bearings with the sander.
  
• Baffling.  See Baffling DS-3.
  

Current issues and future enhancements

• Weight.  After much consideration, I have decided to leave this scope's weight alone.  The obvious areas that I could lighten up the scope are the mirror box, the rocker box and the ground board.  If the mirror box is lightened any more I will have to increase the size of the bearings, which won't let the scope fit into my car.  If I lighten up the rocker box and change it's stiffness, I will probably introduce vibration into the system.  And the ground board isn't worth worrying about.  So, from a weight perspective, DS-3 is finished.