Bob's Knobs for Vixen VMC200L Catadioptric Secondary

Bob's Knobs for Vixen VMC200L Catadioptric Secondary
Item # BS-VMC200SEC
2 Questions(s)

Waiting List

  • This set of three Bob's Knobs will fit the Vixen VMC200L Catadioptric secondary. It does not fit the VC200L, just the VMC.
  • Knobs are made of black plastic, and measures 16 mm (5/8 inch) in diameter. The threads are made of stainless steel.


Bob's Knobs for Vixen VMC200L Catadioptric Secondary

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. And 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.

Note1: Bob's Knobs sit very close to the secondary housing so the factory dust cover should fit fine. However, if the knobs contact the secondary housing before the screws reach the secondary mirror, the manufacturer can supply knobs with longer screws at no charge. If the knobs interfere with the dust cover a shower cap can be used as a substitute cover.

Bob's Knobs Product Number: VMC200SEC
Additional Information

Additional Information

Manufacturer Bob's Knobs
Barrel Size Knob-Style
Collimation Knobs For... Vixen Telescopes
For What Telescopes? Cassegrains
Warranty Lifetime Warranty
Included Items

Included Items

  • Set of 3 Bob's Knobs for Vixen VMC200L
Questions & Answers

Product Questions

After replacing the stock collimation screws with those of Bob's Knobs the dust cover no longer fits. The Bob's Knobs screws protrude out too far even after tightening them to where they feel solid against the secondary mirror cell. What can be done?
How do I safely remove the Vixen logo sticker/ cover that hides the secondary mirror's collimation screws so that I can replace the stock screws with Bob's Knobs' screws?
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