Bob's Knobs Celestron C6 Collimation Knobs
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Bob's Knobs Celestron C6 Collimation Knobs

  (2 Reviews)
✓ 2 year warranty


3x in stock shipped 1-2 working days

About this product

Model:  bk_c6_met_bo
Part Number:  C6BO

Bob's Knobs are the BEST option for tool-free collimation.

Simple to fit and easy to use.

Collimate your telescope without an Allen key or screwdriver! 

Instructions are supplied but can also be found online as well as useful FAQ.

Images are representative and may not show the exact knob size / threads.

IMPORTANT: Please ensure the Bob's knobs threads and factory screw threads match before installation. 

C6 f/10 Secondary with Metric Collimation Screw Threads

Part: C6BO (black oxide steel); C6SS (stainless steel)
Fits: Celestron 6” (15 cm) f/10 SCT versions (C6-A-XLT, C6-GT, C6-S, C6-SE, C6-SGT, others)

Knobs: Black oxide steel (black) or stainless steel (silver), 12 mm (1/2”) diameter
Threads: Black oxide or stainless steel

  1. All versions of the Celestron C6 SCT have collimation screws with metric threads.
  2. Black oxide steel (shown in photo) is for dry environments. Lightly oil the knobs periodically as an anti-corrosion measure. Stainless steel provides better corrosion protection in coastal or high humidity areas, or in places where dew or other condensation is common.
  3. The factory dust cover will usually fit properly with Bob’s Knobs installed. However, some very early versions of this design have very little clearance between the factory dust cover and the secondary housing. To make room for the knobs, contact us for a free set of spacers that attach to the ring around the corrector plate to move the dust cover slightly away from the secondary assembly. These spacers are not needed for most versions of this telescope.

Customer reviews

Average Rating (2 Reviews):  
Write a Review and share your opinions!

Rating (max 5):  
great product
18 August 2022  | 

Trying to collimate with a screwdriver I found to be difficult, with Bobs Nobs it took a few minutes so I bought two sets one for my Celestron 6SE and one for my Celestron Fi5

Rating (max 5):  
Easy Collimation
23 September 2020  | 

I bought these due to the screws on my Celestron SE6 being stuck eventually released by applying WD40 in the dark. Not wanting to ever repeat this I purchased Bob's knobs, these arrived promptly by post, came with great instructions one fitted I recollimated by looking through the eyepiece and tweaking these. Perfect collimation in minutes and no WD40 involved.
Perfect both in both the supply and the product. Thanks FLO, and of course Bob.


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