Bob's Knobs for Vixen R200SS Primary
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Collimate your Catadioptric or Newtonian reflector style telescopes without tools!
It's easy...just grab a Bob's Knob collimation thumbscrew and turn. You can even do it while looking through the eyepiece on most scopes. These thumbscrews are also much easier to use with gloves on. And perhaps most importantly, you'll never drop that pesky little Allen wrench or screwdriver into the grass again. Installation is a snap with the included instructions, and you can undo the modification at any time.
Part: R200pri
Fits: Vixen R200SS telescopes, GSO 4.5" f/12 Classical Cassegrain.
Primary collimation
- Knobs: Black plastic, 13 mm (1/2") diameter
- Threads: Stainless steel
Primary Lock
- Knobs: Red plastic, 16 mm (5/8") diameter
- Threads: Stainless steel
Notes:
- Since the factory collimation and locking screws are close together, knobs must be staggered in height. The locking knobs protrude further than the collimation knobs. Locking knobs are now red for easy identification.
- Early versions of the R200SS primary use metric M5 screws for primary adjust instead of the M4 screws that we provide. You can pull a primary adjust screw, which is the Phillips screw, and measure the thread diameter. If you need M5 primary adjust screws with your knobs, please enter a note in the window provided during checkout.
- Protect the locking knobs from damage, and do not support the OTA using the locking knobs as feet.
Other Information
- Country of Manufacture: United States
Collimate your Catadioptric or Newtonian reflector style telescopes without tools!
It's easy...just grab a Bob's Knob collimation thumbscrew and turn. You can even do it while looking through the eyepiece on most scopes. These thumbscrews are also much easier to use with gloves on. And perhaps most importantly, you'll never drop that pesky little Allen wrench or screwdriver into the grass again. Installation is a snap with the included instructions, and you can undo the modification at any time.
Part: R200pri
Fits: Vixen R200SS telescopes, GSO 4.5" f/12 Classical Cassegrain.
Primary collimation
- Knobs: Black plastic, 13 mm (1/2") diameter
- Threads: Stainless steel
Primary Lock
- Knobs: Red plastic, 16 mm (5/8") diameter
- Threads: Stainless steel
Notes:
- Since the factory collimation and locking screws are close together, knobs must be staggered in height. The locking knobs protrude further than the collimation knobs. Locking knobs are now red for easy identification.
- Early versions of the R200SS primary use metric M5 screws for primary adjust instead of the M4 screws that we provide. You can pull a primary adjust screw, which is the Phillips screw, and measure the thread diameter. If you need M5 primary adjust screws with your knobs, please enter a note in the window provided during checkout.
- Protect the locking knobs from damage, and do not support the OTA using the locking knobs as feet.
Collimate your Catadioptric or Newtonian reflector style telescopes without tools!
It's easy...just grab a Bob's Knob collimation thumbscrew and turn. You can even do it while looking through the eyepiece on most scopes. These thumbscrews are also much easier to use with gloves on. And perhaps most importantly, you'll never drop that pesky little Allen wrench or screwdriver into the grass again. Installation is a snap with the included instructions, and you can undo the modification at any time.
Part: R200pri
Fits: Vixen R200SS telescopes, GSO 4.5" f/12 Classical Cassegrain.
Primary collimation
- Knobs: Black plastic, 13 mm (1/2") diameter
- Threads: Stainless steel
Primary Lock
- Knobs: Red plastic, 16 mm (5/8") diameter
- Threads: Stainless steel
Notes:
- Since the factory collimation and locking screws are close together, knobs must be staggered in height. The locking knobs protrude further than the collimation knobs. Locking knobs are now red for easy identification.
- Early versions of the R200SS primary use metric M5 screws for primary adjust instead of the M4 screws that we provide. You can pull a primary adjust screw, which is the Phillips screw, and measure the thread diameter. If you need M5 primary adjust screws with your knobs, please enter a note in the window provided during checkout.
- Protect the locking knobs from damage, and do not support the OTA using the locking knobs as feet.
Other Information
- Country of Manufacture: United States
Bob's Knobs for Vixen R200SS Primary