Samyang/Rokinon 135mm Rings + Fine Bahtinov Mask

Summary

This is a (almost) fully 3d-printable kit of rings to connect the Samyang/Rokinon 135mm f/2.0 lens onto a light and small star tracker (such as the Sky Watcher Star Adventurer) or an equatorial mount (such as the Sky Watcher EQ6).

Once everything is printed and put together you just slide the lens in, and tighten the two knobs. Since the rings are a bit bigger than the lens, you must use some rubber/felt tape on the innner part of them.

The Vixen-style lower plate has 4 rails designed to move the rings. With the camera attached you can achieve balance when mounted on a ¼ of Inch thread (Sky Watcher Star Adventurer style). In my case, I used the included ⅜ to ¼ of Inch adapter welded in place with a soldering station.

The Bahtinov Mask is designed using the SVG generator by Satoru Takagi and has a very fine pattern (prints OK with 0.4mm nozzle), perfect for bigger diffraction spikes.

I also uploaded the STEP file, including all the bodies.

The majority of the parts were remixed from this project and this other one from Thingiverse.

Bill Of Materials

• Screws:
  M4x12mm Allen countersunk head (6 pcs; top plate + hinges)
  M4x50mm Hex head (2 pcs; knobs)
  M5x20mm Allen head (4 pcs; vixen plate)
• Nuts:
  M4 Hex nuts (6 pcs; top plate + knobs)
  M4 Self-locking nuts (2 pcs; hinges)
  M5 Hex nuts (4 pcs; vixen plate)
• Necessary:
  70mm Ring Base (1 pc)
  70mm Ring Top (1 pc)
  80mm Ring Base (1 pc)
  80mm Ring Top (1 pc)
  Knob (2 pcs)
  Top Plate (1 pc)
  Vixen Plate (1 pc)
• Optional:
  Bahtinov Mask (1 pc)

Print Settings

• 0.4mm Nozzle Diameter
• 0.2mm Layer Height
• 25% Infill
• Supports where needed