Bob's Knobs for Orion XT 4-Vane Phillips Screw Secondary
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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: CNsec25
Fits: Orion SkyQuest XT-series with factory long Phillips secondary collimation screws. This configuration is not as common as the set-screw secondary.
Secondary Characteristics: 4-vane spider, a deeply recessed center screw, and factory Phillips collimation screws. The secondary plate holding the screws is about 20 mm (3/4") thick.
Knobs: Black plastic, 13 mm (1/2") diameter
Threads: Stainless steel
Notes:
1. The factory collimation screw length, measured below the head, can be either 25 mm or 32-35 mm. Order knobs with the correct screw length for your application, which is usually 35 mm. This secondary is somewhat rare on the XT-series.
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: CNsec25
Fits: Orion SkyQuest XT-series with factory long Phillips secondary collimation screws. This configuration is not as common as the set-screw secondary.
Secondary Characteristics: 4-vane spider, a deeply recessed center screw, and factory Phillips collimation screws. The secondary plate holding the screws is about 20 mm (3/4") thick.
Knobs: Black plastic, 13 mm (1/2") diameter
Threads: Stainless steel
Notes:
1. The factory collimation screw length, measured below the head, can be either 25 mm or 32-35 mm. Order knobs with the correct screw length for your application, which is usually 35 mm. This secondary is somewhat rare on the XT-series.
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: CNsec25
Fits: Orion SkyQuest XT-series with factory long Phillips secondary collimation screws. This configuration is not as common as the set-screw secondary.
Secondary Characteristics: 4-vane spider, a deeply recessed center screw, and factory Phillips collimation screws. The secondary plate holding the screws is about 20 mm (3/4") thick.
Knobs: Black plastic, 13 mm (1/2") diameter
Threads: Stainless steel
Notes:
1. The factory collimation screw length, measured below the head, can be either 25 mm or 32-35 mm. Order knobs with the correct screw length for your application, which is usually 35 mm. This secondary is somewhat rare on the XT-series.
Other Information
- Country of Manufacture: United States
Bob's Knobs for Orion XT 4-Vane Phillips Screw Secondary