Bob's Knobs for C11 f/10 with “Trifid” Fastar Secondary Housing and Metric Collimation Screw Threads
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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: C11metfst
Fits: Celestron 11” (28 cm) f/10 SCT versions (metal or carbon fiber tube) with metric thread factory collimation screws and Fastar secondary housing. This housing can have either a "Trifid" rotary cover ( second photo above) or a simple knob in the center (fourth photo) and no rotary cover. Factory collimation screws are black Phillips. These knobs will fit the C11 with EdgeHD optics (third photo). They will also fit the C11 with Starizona Hyperstar (fifth photo) only if the collimation screws have metric threads.
Knobs: Black plastic, 16 mm (5/8”) diameter
Threads: Stainless steel
Notes:
- These telescopes can have factory collimation screws with either standard or metric threads. Most models with black Phillips collimation screws have metric threads. There are a few black Phillips screws with standard threads. See our hints for more information. If you discover your knobs have the wrong threads, you can return them for a refund and order the correct knobs. Alternatively, you can order knobs with both standard and metric thread screws and return the unused set for a full refund.
- Collimation screws on these telescopes are small with very fine threads. Knobs must be tightened gently (just enough to hold the secondary in place) to prevent damage to either the knob or secondary assembly.
- The factory dust cover will fit normally with Bob’s Knobs installed.
- If your telescope has a rotary secondary cover, it must remain open when the knobs are installed. The cover is cosmetic only and will not affect operation of the telescope.
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: C11metfst
Fits: Celestron 11” (28 cm) f/10 SCT versions (metal or carbon fiber tube) with metric thread factory collimation screws and Fastar secondary housing. This housing can have either a "Trifid" rotary cover ( second photo above) or a simple knob in the center (fourth photo) and no rotary cover. Factory collimation screws are black Phillips. These knobs will fit the C11 with EdgeHD optics (third photo). They will also fit the C11 with Starizona Hyperstar (fifth photo) only if the collimation screws have metric threads.
Knobs: Black plastic, 16 mm (5/8”) diameter
Threads: Stainless steel
Notes:
- These telescopes can have factory collimation screws with either standard or metric threads. Most models with black Phillips collimation screws have metric threads. There are a few black Phillips screws with standard threads. See our hints for more information. If you discover your knobs have the wrong threads, you can return them for a refund and order the correct knobs. Alternatively, you can order knobs with both standard and metric thread screws and return the unused set for a full refund.
- Collimation screws on these telescopes are small with very fine threads. Knobs must be tightened gently (just enough to hold the secondary in place) to prevent damage to either the knob or secondary assembly.
- The factory dust cover will fit normally with Bob’s Knobs installed.
- If your telescope has a rotary secondary cover, it must remain open when the knobs are installed. The cover is cosmetic only and will not affect operation of the telescope.
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: C11metfst
Fits: Celestron 11” (28 cm) f/10 SCT versions (metal or carbon fiber tube) with metric thread factory collimation screws and Fastar secondary housing. This housing can have either a "Trifid" rotary cover ( second photo above) or a simple knob in the center (fourth photo) and no rotary cover. Factory collimation screws are black Phillips. These knobs will fit the C11 with EdgeHD optics (third photo). They will also fit the C11 with Starizona Hyperstar (fifth photo) only if the collimation screws have metric threads.
Knobs: Black plastic, 16 mm (5/8”) diameter
Threads: Stainless steel
Notes:
- These telescopes can have factory collimation screws with either standard or metric threads. Most models with black Phillips collimation screws have metric threads. There are a few black Phillips screws with standard threads. See our hints for more information. If you discover your knobs have the wrong threads, you can return them for a refund and order the correct knobs. Alternatively, you can order knobs with both standard and metric thread screws and return the unused set for a full refund.
- Collimation screws on these telescopes are small with very fine threads. Knobs must be tightened gently (just enough to hold the secondary in place) to prevent damage to either the knob or secondary assembly.
- The factory dust cover will fit normally with Bob’s Knobs installed.
- If your telescope has a rotary secondary cover, it must remain open when the knobs are installed. The cover is cosmetic only and will not affect operation of the telescope.
Other Information
- Country of Manufacture: United States
Bob's Knobs for C11 f/10 with “Trifid” Fastar Secondary Housing and Metric Collimation Screw Threads