Bob's Knobs for Celestron C11 f/10 with Flat Secondary Housing and Metric Collimation Screw Threads
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Special Note: The Celestron 11" SCT uses either standard 6-32 or metric M3 collimation screws. Allen and set-style factory collimation screws have standard threads. For Phillips collimation screws, most silver screws are standard and most black screws are metric. See our hints for more information.
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: C11metBO
Fits: Celestron 11” (28 cm) f/10 SCT versions with flat secondary housing and metric collimation screw threads (most CPC 1100). Does not fit the Starizona Hyperstar secondary (see Item C11metfst).
Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel
Notes:
- Black Phillips factory collimation screws (second photo) usually have metric threads, but some black Phillips screws have standard threads. Our hints will help you determine which screws are on your telescope. Make sure the knob threads match the factory screw threads before installing the knobs.
- Black oxide steel is for dry environments. Lightly oil the knob top and knob serrations periodically as an anti-corrosion measure.
- The factory dust cover will fit normally with Bob's Knobs installed.
- If your telescope has a factory-installed plastic cap over the collimation screws, it must be removed and set aside when Bob's Knobs are installed. The cover is cosmetic only and will not affect operation of the scope.
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: C11metBO
Fits: Celestron 11” (28 cm) f/10 SCT versions with flat secondary housing and metric collimation screw threads (most CPC 1100). Does not fit the Starizona Hyperstar secondary (see Item C11metfst).
Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel
Notes:
- Black Phillips factory collimation screws (second photo) usually have metric threads, but some black Phillips screws have standard threads. Our hints will help you determine which screws are on your telescope. Make sure the knob threads match the factory screw threads before installing the knobs.
- Black oxide steel is for dry environments. Lightly oil the knob top and knob serrations periodically as an anti-corrosion measure.
- The factory dust cover will fit normally with Bob's Knobs installed.
- If your telescope has a factory-installed plastic cap over the collimation screws, it must be removed and set aside when Bob's Knobs are installed. The cover is cosmetic only and will not affect operation of the scope.
Special Note: The Celestron 11" SCT uses either standard 6-32 or metric M3 collimation screws. Allen and set-style factory collimation screws have standard threads. For Phillips collimation screws, most silver screws are standard and most black screws are metric. See our hints for more information.
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: C11metBO
Fits: Celestron 11” (28 cm) f/10 SCT versions with flat secondary housing and metric collimation screw threads (most CPC 1100). Does not fit the Starizona Hyperstar secondary (see Item C11metfst).
Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel
Notes:
- Black Phillips factory collimation screws (second photo) usually have metric threads, but some black Phillips screws have standard threads. Our hints will help you determine which screws are on your telescope. Make sure the knob threads match the factory screw threads before installing the knobs.
- Black oxide steel is for dry environments. Lightly oil the knob top and knob serrations periodically as an anti-corrosion measure.
- The factory dust cover will fit normally with Bob's Knobs installed.
- If your telescope has a factory-installed plastic cap over the collimation screws, it must be removed and set aside when Bob's Knobs are installed. The cover is cosmetic only and will not affect operation of the scope.
Other Information
- Country of Manufacture: United States
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Bob's Knobs for Celestron C11 f/10 with Flat Secondary Housing and Metric Collimation Screw Threads