2-inch to STL Thread Adapter

#17667 - 2-inch to 2.156"x24tpi male thread Adapter.

2-inch to STL AdapterThe 2-inch to STL thread adapter was developed to easily adapt the SBIG and QSI cameras and filters wheels for the TCF-S focuser.

By holding tight tolerances (+/- 0.003") Optec has achieved a slip-fit that is second-to-none.  When used with the TCF-S focuser, the #17667 with its  precision machined dovetail cut exactly matches the three thumbscrews on the focuser's  drawtube.  By tightening the thumbscrews, the dovetail is drawn tighter to the face of the drawtube completely eliminating flexure.

  • Overall Outside Diameter:  2.45" (62mm)
  • Outside Diameter (drawtube body):  1.995" (50.7mm)
  • Overall Height: 1.34" (34mm)
  • Height of 2.156"x24 threads:  0.24"  (6.1mm)
  • Clear Aperture: 1.70" (43mm)
  • Weight: 1.4 oz (35 g)
  • Back-focus Usage: 0.10" (2.75 mm)
Compatible with:
  • TCF-S or TCF-Si focuser,
  • TCF-S3 or TCF-S3i focuser with #17804 3-inch to 2-inch reducer,
  • Any manufacturer's 2-inch focuser or receiver,
  • M48x0.6mm threaded filters.
How to Order:

Contact any Optec dealer, call Toll-Free 1-888-488-0381, email, or visit our ecommerce site: optecinc.us.

Additional Product Views:

2-inch to STL Adapter 2-inch to STL Adapter  2-inch to STL Adapter
2-inch to STL Adapter2-inch to STL Adapter

So what is the purpose of that little brass screw?  To allow rotational alignment when removing and re-inserting a camera system in the dark, the TCF-S and JMI focusers have registration notch.  If your focuser does not have a mating notch, simply remove the brass screw with a flat-tip screwdriver and discard.

Adapter Drawings:

Adobe 3D PDF Adobe 3D PDF


Other 2-inch Drawtube Mounts