OpenScope MK II F5 Newtonian Telescope

A 3D printable F5 Newtonian telescope with an open or closed frame design and support for autofocusing designed for astrophotography or visual observing.

Designed to support A6 inch primary mirror and can be customized to support multiple focal lengths.

Utilizes a remix of a 3D printed 2-inch Crayford focuser to allow for a belt-driven auto focuser system driven by a NEMA 17 stepper.

supports a standard dovetail mounting rail for compatibility with most computerized goto tracking mounts.

Bill of materials:

• ~1kg PLA
• 3 1515 makerbeams length depends on the focal length of the primary mirror.
• 18 M3x8
• 18 M3 square nuts (these need to be compatible with the 1515 extrusions)
• 9 8mm OD 20mm length springs (six can be substituted for 3D printed 20mm long spacers)
• 6 M4x35
• 3 M4x40 hex bolt
• 3 M4 wingnut
• 4 M3x12
• 12 M3 threaded insert
• 11 M4 threaded insert
• 3 M3x30
• 1 M3x45
• 4 M6x30
• 4 M6 locking nut
• 1 GT2 40T pully
• 1 GT2 16/20T pully
• 1 GT2 200mm belt
• All parts listed in the focuser BOM
• 1 6-inch primary telescope mirror (highly recommend a parabolic mirror see link)
• 1 2-inch angled secondary mirror (well usually comes with the primary)

Optional items

• 8-inch concrete sonotube
• 2-inch coma corrector (especially if using the scope for astrophotography)
• Dovetail mounting bracket.

I have included the files for the focuser that I've modified the rest should be found on his website that I've linked below.

I've also included the CAD files for the entire project.

An assembly guide will come shortly.

Edit 09OCT22

added more photos

Links

https://marcosatm.com/2020/06/04/2in-crayford-focuser/

https://agenaastro.com/gso-parabolic-primary-telescope-mirror-6-f-5-ad046.html