Bob's Knobs for Celestron C6 f/10 Secondary with 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 cane ven do it while looking through the eyepiece on most scopes. These thumbscrews are also much easier to use with gloves on. And perhaps the most importantly, you'll never drop that pesky little Allen wrench or screwdriver into the grass agin. Installation is a snap with the included intructions an you can undo the modifications any time.
Part: C6BO
Fits: Celestron 6" (15 cm) f/10 SCT versions (C6 Evolution, C6-A-XLT, C6-GT, C6-S, C6-SE, C6-SGT, others)
Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel
Notes:
- All versions of the Celestron C6 SCT have collimation screws with metric threads.
- Secondary collimation screws have threads (measured below the screw head) that are either 10 mm or 12 mm long. We include a set of white spacers to be used on the knobs if factory threads are 10 mm long. Do NOT use the white spacers if the factory screw threads are 12 mm long.
- 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 usually fit properly with Bob’s Knobs installed, except on some very early versions.
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 cane ven do it while looking through the eyepiece on most scopes. These thumbscrews are also much easier to use with gloves on. And perhaps the most importantly, you'll never drop that pesky little Allen wrench or screwdriver into the grass agin. Installation is a snap with the included intructions an you can undo the modifications any time.
Part: C6BO
Fits: Celestron 6" (15 cm) f/10 SCT versions (C6 Evolution, C6-A-XLT, C6-GT, C6-S, C6-SE, C6-SGT, others)
Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel
Notes:
- All versions of the Celestron C6 SCT have collimation screws with metric threads.
- Secondary collimation screws have threads (measured below the screw head) that are either 10 mm or 12 mm long. We include a set of white spacers to be used on the knobs if factory threads are 10 mm long. Do NOT use the white spacers if the factory screw threads are 12 mm long.
- 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 usually fit properly with Bob’s Knobs installed, except on some very early versions.
Collimate your Catadioptric or Newtonian reflector style telescopes without tools!
It's easy....just grab a Bob's Knob collimation thumbscrew and turn. You cane ven do it while looking through the eyepiece on most scopes. These thumbscrews are also much easier to use with gloves on. And perhaps the most importantly, you'll never drop that pesky little Allen wrench or screwdriver into the grass agin. Installation is a snap with the included intructions an you can undo the modifications any time.
Part: C6BO
Fits: Celestron 6" (15 cm) f/10 SCT versions (C6 Evolution, C6-A-XLT, C6-GT, C6-S, C6-SE, C6-SGT, others)
Knobs: Black oxide steel, 12 mm (1/2") diameter
Threads: Black oxide steel
Notes:
- All versions of the Celestron C6 SCT have collimation screws with metric threads.
- Secondary collimation screws have threads (measured below the screw head) that are either 10 mm or 12 mm long. We include a set of white spacers to be used on the knobs if factory threads are 10 mm long. Do NOT use the white spacers if the factory screw threads are 12 mm long.
- 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 usually fit properly with Bob’s Knobs installed, except on some very early versions.
Other Information
- Country of Manufacture: United States
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Bob's Knobs for Celestron C6 f/10 Secondary with Metric Collimation Screw Threads


















