CNC Manufactured AstroGoods.

New Products

Low cost standardized mounts.
Rotating rings for GEMs.
4.25" mirror cells - soon.

Primary mirror masks.

Crystal 909 bearing laminate.

  • Limited Time End Of Summer Pricing.
  • Low cost standard mounts with bearings.
  • Custom mounts to improve performance.
  • SCT and other OTAs on Dob mounts.
  • Limited Time End Of Summer Pricing.
  • 6" - 13.1" optimized to your mirror's spec.
  • Universal cells for conical/standard mirrors.

Altitude Bearings

  • Swap small bearings for large ones.
  • Small bearings fitted to your tube O.D.
  • Large bearings for tubes or mirror boxes.
  • Add bearings to Newtonian ring sets.
  • Bearing supports.

Clamshell Rings

  • Equatorial head mounting your Dob OTA.
  • Clamshell Rings and Bearings.
  • Lightweight rings for smaller telescopes.
  • Alt and Az bearing laminate strips and rings.
  • Teflon Alt and Az pads.
  • Aluminum tubes.
  • Tube end protectors.

Streetlight Baffles

  • Keep stray light away from your focuser.
  • FRP azimuth disks and rings.

New Products
E-Mail for shipping estimates

Primary Mirror Masks

Primary mirror masks are 0.25" thick baltic birch plywood rings that you paint and Velcro to the top of the mirror clips of your mirror cell. Each is custom cut to precisely cover from the outside edge of your mirror clips to the inside diameter of the mirror clip intrusion over the mirror, resulting in a perfect unbroken circle over the mirror and hiding any turned edge on the primary. Just provide the inside and outside diameter of the mirror clips. Masks up to 12.5" OD are $25 plus shipping.

Inside diameter:
Outside diameter:

GEM Tube Rotating Rings Rotating Rings design (clickable image left) is based on our Clamshell Rings, combining the heavy duty and light weight ring.

The Tube Ring (yellow) is cut to fit within 1/16" of your tube outside diameter. Apply adhesive backed felt inside the ring until the fit is tight enough to prevent any tube movement inside the Tube Rings.

The Tube Rings and tube then fit into the opened Clamshell Rings, in a recess between the outside of the clamshell and the overlapping retainers. The clamshell rings are then closed. The Tube Rings ride inside against an FRP ring on the face of the clamshell. Four adjustments per ring set are available to fine tune the movement; two in the Retainers and two on the outside of the Clamshell Rings allowing tension of the assembly as desired. The Clamshell Ring is designed to match the hole pattern on your mount.

Kit and Finished: Available as a kit which you finish sand and paint, or finished which arrives ready to use. Below are maximum tube sizes for each price.

GEM Rotating Rings
Tube Circumference?