Dome Ring V 1.1

Wasn’t real happy with the dome ring as it was in the previous post.  It “worked”, but had 2 issues :

  • The inside surface of the ring, which rides against the “retaining posts” wasn’t as smooth as it should have been.  This resulted in bumps and jumps whenever it was spinning the PVC “bearings” of the retaining posts.
  • As a result of the ring being comprised of 16 45° sections, the inside circle was 1/4″-3/8″ out of round.  So, in some places, the ring would be tight against all 3 retaining posts, which would cause friction and stiffness.  In other places, there was a good 1/2″ gap between the ring and at least 2 of the retaining posts.  End result : depending on where you started the ring, you could get a good 1/2″ of lateral “shift” in the ring before it started rotating.

While both of these conditions would still allow the dome to rotate, they weren’t ideal.  Figuring now’s the time to fix minor issues while I can, I’ve taken 3 steps to address these issues :

  • A center was marked on a platform placed in the middle of the ring, and a router on a DIY trammel used to route a clean good circle out of the inside of the ring.  This took 1/4-1/2″ or so off the inside surface all around, and left me with a ring closer to true round.
  • 1/8″ Masonite is now being glued to the inside surface, tempered (smooth) side facing out, to provide a much smoother surface for the retaining posts to ride on.
  • The retaining posts were previously just PVC pipe slid over 1/2″ bolts.  They will be replaced with 1/4″ ID bearings over 1/4-20 lag bolts, and the Masonite will contact the outer diameter of the bearings directly.
This entry was posted in Dome Project. Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *