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Bobs Knobs

Items 26 - 50 of 67

Bob's Knobs Meade 16" SCT Collimation Knobs For 3-Screw Secondary - M16-3

SKU: BOB-M16-3
  • These Bob's Knobs Collimation Knobs are designed to fit Meade 16" f/10 Schmidt-Cassegrain telescope models with 3-screw secondary housing like the LX200.
  • Each knob in this set measures 16 mm or 5/8" in diameter and is made of black plastic.
  • The factory supplied dust cover will fit as per usual with these collimation knobs installed.
  • Comes with an Allen wrench for factor collimation screw removal.
  • Meade 16" SCTs with 6-screw secondary housing require a different set of knobs.
$25.95 $20.76

Bob's Knobs Meade 16" SCT Collimation Knobs For 6-Screw Secondary - M16-6

SKU: BOB-M16-6
  • Bob's Knobs Collimation Knobs designed for Meade 16" f/10 Schmidt-Cassegrain telescope models with 6-screw secondary housing such as the LX200
  • These stainless steel collimation knobs measure 19 mm or 3/4" in diameter.
  • The factory supplied dust cover will fit as per usual with these collimation knobs installed.
  • Comes with an Allen wrench for factor collimation screw removal.
  • Meade 16" SCTs with 3 screws on the secondary housing require a different set of knobs.
$25.95

Bob's Knobs Meade 6" SCT f/10 Collimation Knobs For 6-Screw Secondary - M6-6

SKU: BOB-M6-6
  • These Bob's Knobs Collimation Knobs are designed to fit Meade 6" f/10 Schmidt-Cassegrain telescopes such as the LS-6 SC and LS-6 ACF models.
  • The factory supplied dust cover will fit as per usual with these collimation knobs installed.
  • Comes with an Allen wrench for factor collimation screw removal.
  • Installation instructions are included.
$25.95

Bob's Knobs 8" Meade SCT 3-Screw Secondary - M8-3

SKU: BOB-M8-3
  • Measuring 13 mm or 1/2" in diameter, these Bob's Knobs Collimation Knobs are designed to fit Meade 8" f/8 Schmidt-Cassegrains with 3 screws on the secondary housing such as LX5, LX10, LX50, LX90, LX100, LX200, and 2080 model telescopes.
  • Made of black plastic with black anodized aluminum alloy threads.
  • Comes with an Allen wrench for factor collimation screw removal.
  • A set of spacers to be attached to the inside of your telescope's factory dust cover is also provided to ensure that the dust cover fits properly.
$16.00

Bob's Knobs Meade 8" SCT Collimation Knobs For 4-Screw Secondary - M8-4

SKU: BOB-M8-4
  • Measuring 13 mm or 1/2" in diameter, these Bob's Knobs Collimation Knobs are designed to fit Meade 8" f/10 Schmidt-Cassegrain telescopes with 4-screw secondary housing such as the LX90 and LX200 models among others.
  • Made of black plastic with black anodized aluminum alloy threads.
  • Comes with an Allen wrench for factor collimation screw removal.
  • A set of spacers to be attached to the inside of your telescope's factory dust cover is also provided to ensure that the dust cover fits properly.
  • Meade 8" SCTs produced before 2005 with 3 screws on the secondary housing and no 4th screw on the side require a different set of collimation knobs.
$16.95

Bob's Knobs for Meade 8" SCT with 6-Screw Thread - M8-6

SKU: BOB-M8-6
  • Measuring 13 mm or 1/2" in diameter, these Bob's Knobs Collimation Knobs are designed to fit Meade 8" f/10 Schmidt-Cassegrain telescopes with 6 screws on the secondary housing such as the LX90, LX200, LX200R, and LX200ACF models.
  • Made of black plastic with black anodized aluminum alloy threads.
  • Comes with an Allen wrench for factor collimation screw removal.
  • A set of spacers to be attached to the inside of your telescope's factory dust cover is also provided to ensure that the dust cover fits properly.
  • Some Meade 8" SCTs produced before 2005 have 3 screws on the secondary housing and thus require a different set of collimation knobs.
$16.00

Bob's Knobs Meade 8" SCT Widefield f/6.3 Collimation Knobs W/ Dust Cover Spacers - M8WF

SKU: BOB-M8WF
  • These Bob's Knobs Collimation Knobs fit Meade 8" Schmidt-Cassegrain telescope models including the LX6, LX10, LX50, LX100, LX200, and 2080 models with f/6.3 Wide Field marked on the corrector ring.
  • Each knob in this set measures 12 mm or 1/2" in diameter and features stainless steel construction.
  • Comes with an Allen wrench for factor collimation screw removal.
  • A set of spacers to be attached to the inside of your telescope's factory dust cover is also provided to ensure that the dust cover fits properly.
$25.95 $20.76

Bob's Knobs Meade 10" Lightbridge Collimation Knobs For Primary Screws - MLB10pri

SKU: BOB-MLB10PRI
  • These Bob's Knobs Collimation Knobs are designed to fit the primary screws on the Meade 10" f/5 LightBridge Dobsonian reflector telescope.
  • Collimation knobs are 5-point fluted, measure 30 mm in diameter, and have plated steel threads.
  • Knurled lock knobs measure 25 mm in diameter and have stainless steel threads.
  • With these knobs installed, the OTA will still be able to clear the rocker box.
$27.95

Bob's Knobs Meade 12" Lightbridge Low Profile AZ Lock 5/16" - MLB12AZ1

SKU: BOB-MLB12AZ1
  • This lock from Bob's Knobs are meant to work with Meade 12" LightBridge Low Profile AZ Lock.
  • Bob's Knobs lock works with the low-profile design of the Meade 12" LightBridge rocker box.
  • This knob is make od black plastic with stainless steel threads.
  • The lock bolt diameter is 5/16".
$9.95

Bob's Knobs Meade 12" Lightbridge Low Profile AZ Lock 3/8" - MLB12AZ2

SKU: BOB-MLB12AZ2
  • This lock from Bob's Knobs are meant to work with Meade 12" LightBridge Low Profile AZ Lock.
  • Bob's Knobs lock works with the low-profile design of the Meade 12" LightBridge rocker box.
  • This knob is make od black plastic with stainless steel threads.
  • The lock bolt diameter is 3/18".
$9.95 $7.96

Bob's Knobs Springs for Meade 8", 10" & 12" Lightbridge - CNSPR

SKU: BOB-CNSPR
  • These springs from Bob's Knobs are meant to work with Meade 8", 10" & 12" Lightbridge telescopes.
  • Bob's Knobs Meade Lightbridge springs are meant to help provide adequate support to maintain primary mirror collimation.
  • Included in the kit are three metal springs.
  • Bob's Knobs are designed to be stronger than the standard springs.
$16.95

Bob's Knobs Meade Starfinder 10" Collimation Knobs - Primary Screws - MSF10PRI

SKU: BOB-MSF10PRI
  • These primary collimation knobs from Bob's Knobs are designed for the Meade 10" Starfinder reflector telescope.
  • Each knob in this set measures 38 mm or 1 1/2" in diameter.
  • Made of black plastic with stainless steel threads.
  • Knobs are available for the Starfinder primary only as the secondary arrangement interferes with them.
$27.95

Bob's Knobs Meade SNT 6" Collimation Knobs - Secondary Screws - MSN6SEC

SKU: BOB-MSN6SEC
  • Set of collimation knobs from Bob's Knobs designed for the Meade 6" f/5 SNT telescope's secondary mirror.
  • Measuring 13 mm (1/2") in diameter, these knobs feature black plastic construction and stainless steel threads.
  • The factory supplied dust cover will fit as per usual with these collimation knobs installed.
  • Sitting above the lip of the secondary housing, these knobs are easily accessible.
$20.95 $16.76

Bob's Knobs Meade SNT 8" Collimation Knobs Secondary Screws - MSN8SEC

SKU: BOB-MSN8SEC
  • Set of collimation knobs from Bob's Knobs designed for the Meade 8" f/4 SNT telescope's secondary mirror.
  • Measuring 13 mm (1/2") in diameter, these knobs feature black plastic construction and stainless steel threads.
  • The factory supplied dust cover will fit as per usual with these collimation knobs installed.
  • Sitting above the lip of the secondary housing, these knobs are easily accessible.
$20.95 $16.76

Bob's Knobs Meade SNT 10" Collimation Knobs Secondary Screws - MSN10SEC

SKU: BOB-MSN10SEC
  • Set of collimation knobs from Bob's Knobs designed for the Meade 10" f/4 SNT telescope's secondary mirror.
  • Measuring 13 mm (1/2") in diameter, these knobs feature black plastic construction and stainless steel threads.
  • The factory supplied dust cover will fit as per usual with these collimation knobs installed.
  • Sitting above the lip of the secondary housing, these knobs are easily accessible.
$20.95

Bob's Knobs Meade 12" Lightbridge Collimation Knobs Primary Screws - MLB12PRI

SKU: BOB-MLB12PRI
  • These Bob's Knobs Collimation Knobs are designed to fit the primary screws on the Meade 12" f/5 LightBridge Dobsonian reflector telescope.
  • Collimation knobs are 5-point fluted, measure 30 mm in diameter, and have plated steel threads.
  • Knurled lock knobs measure 25 mm in diameter and have stainless steel threads.
  • With these knobs installed, the OTA will still be able to clear the rocker box.
  • For some 12" LightBridge models, primary collimation knobs already included with the scope make the Bob's Knobs primary collimation knobs unnecessary.
$27.95

Bob's Knobs Meade 8" Lightbridge Collimation Knobs Primary Screws - MLB8PRI

SKU: BOB-MLB8PRI
  • These Bob's Knobs Collimation Knobs are designed to fit the primary screws on the Meade 8" f/6 LightBridge Dobsonian reflector telescope.
  • Collimation knobs are 5-point fluted, measure 30 mm in diameter, and have plated steel threads.
  • Knurled lock knobs measure 25 mm in diameter and have stainless steel threads.
  • With these knobs installed, the OTA will still be able to clear the rocker box.
$27.95

Bob's Knobs Collimation Knobs for Skywatcher 190mm Mak-Newtonian Primary - MN190PRI

SKU: BOB-MN190PRI
  • This Bob's Knobs primary collimation knob set is designed to fit Sky-Watcher 190 mm Maksutov-Newtonian telescopes.
  • Both the collimation knobs and the lock knobs measure 16 mm or 5/8" in diameter and contain stainless steel threads.
  • Set includes black plastic primary collimation knobs and red plastic primary lock knobs.
  • Knobs must be staggered in height due to the factory collimation and locking screws being so close together.
$25.95

Bob's Knobs Collimation Knobs for Skywatcher 190mm Mak-Newtonian Secondary - MN190SEC

SKU: BOB-MN190SEC
  • Measuring 13 mm or 1/2" in diameter, these Bob's Knobs secondary collimation knobs fit SkyWatcher 190 mm Maksutov-Newtonian telescope.
  • Made from black plastic with stainless steel threads.
  • Mounted on long screws in order to clear the secondary lip.
  • Secondary collimation screws from the factory must be removed prior to installation of these knobs.
$20.95

Bob's Knobs SkyWatcher 5" - 10" & C6, C8, and C10; Newtonian Primary Collimation Knobs - SWPRI

SKU: BOB-SWPRI
  • Measuring 16 mm or 5/8" in diameter, these Bob's Knobs Collimation Knobs fit Orion and Sky-Watcher 5", 6", 8", and 10" Newtonian reflector telescopes.
  • Made of black plastic with stainless steel threads.
  • With these knobs installed, the OTA will still be able to clear the rocker box.
  • These knobs are also compatible with Celestron 6", 8", and 10" Newtonian reflectors as well, whether or not they contain GoTo electronics.
  • Knobs must be staggered in height due to the factory collimation and locking screws being so close together.
$25.95
Bob's Knobs Celestron C8 Classic Orange Tube Collimation Knobs

Bob's Knobs Collimation Knobs for Celestron Pre-1980 Orange SCT - C8ORG

SKU: BOB-C8ORG
  • Black plastic collimation knobs with black anodized aluminum alloy threads from Bob's Knobs for vintage orange tube Celestron C8 Schmidt-Cassegrain telescope models made before 1980.
  • Each knob in this set measures 13 mm or 1/2" in diameter.
  • Two separate sets of knobs with different screw lengths to suit your telescope are included.
  • The factory supplied dust cover should fit as per usual without coming into contact with these collimation knobs.
$20.95
Bob's Knobs Celestron C14 Secondary Collimation Knobs - Phillips Screws w/Metric Threads

Bob's Knobs Celestron f/11 C14 Secondary Collimation Knobs - Metric Phillips - C14METPHI

SKU: BOB-C14METPHI
  • Measuring 15 mm in diameter, these Bob's Knobs collimation knobs fit Celestron C14 Schmidt-Cassegrain telescope models that feature Phillips collimation screws with factory metric threads, whether they have EdgeHD optics or not.
  • Made from black plastic with stainless steel threads.
  • The factory supplied dust cover will fit as per usual with these collimation knobs installed.
  • With these Bob's Knobs Collimation Knobs installed, it is crucial that the rotary secondary cover remain open.
$20.95

Bob's Knobs Collimation Knobs for Orion SkyQuest XT Secondary with 25 mm Screw Length - CNSEC25

SKU: BOB-CNSEC25
  • These Bob's Knobs collimation knobs fit Orion SkyQuest XT Newtonian reflector telescopes with 25 mm long factory collimation screws.
  • Each knob in this set measures 13 mm or 1/2" in diameter.
  • Made from black plastic with stainless steel threads.
  • Compatible with 6", 8", 10", 12", and 16" Orion SkyQuest XT reflectors with 4-vane spider secondary, as well as older model 6", 8", and 10" Orion SkyQuest XT reflectors with 3-vane spider secondary.
$20.95

Bob's Knobs Celestron 11" SCT f/10 Fastar Metric Collimation Knobs - C11METFST

SKU: BOB-C11METFST
  • Measuring 13 mm in diameter, these Bob's Knobs Collimation Knobs fit Celestron 11" f/10 Schmidt-Cassegrain telescopes with metric thread factory collimation screws and a "Trifid" rotary cover Fastar secondary housing.
  • These knobs will also fit the Celestron C11 SCT with EdgeHD optics, as well as the C11 with Starizona Hyperstar provided it has metric threaded collimation screws.
  • Made from black plastic with stainless steel threads.
  • The factory supplied dust cover will fit as per usual with these collimation knobs installed.
  • With these Bob's Knobs Collimation Knobs installed, it is crucial that the rotary secondary cover remain open.
$20.95
Bob's Knobs Celestron 11" SCT f/10 Metric Stainless Steel Knobs

Bob's Knobs Celestron 11" SCT f/10 Metric Stainless Steel Knobs - C11METSS

SKU: BOB-C11METSS
  • These Bob's Knobs Collimation Knobs fit Celestron C11 f/10 SCTs featuring flat secondary housing and metric collimation screw threads.
  • Each knob in this set measures 12 mm or 1/2" in diameter.
  • Construction consists of stainless steel for improved corrosion protection in highly humid conditions.
  • The factory supplied dust cover will fit as per usual with these collimation knobs installed.
  • Prior to installation, please make sure the knob threads and factory screw threads match.
$25.95

Bob’s Knobs understands that telescope collimation can be a struggle for observers new to astronomy, but it is crucial to enjoying your telescope to the fullest. Optics out of alignment, or collimation, yield images with noticeable imperfections. For example, stars will not come to a pinpoint focus and planets will look slightly hazy. The best way to prevent this from happening is to collimate your scope.


To achieve collimation, telescopes often include screws which require a screwdriver to modify the position of the mirrors. Unless you are careful, that screwdriver could scratch your optical tube assembly, or even the optics themselves. Moreover, your OTA’s mirrors are highly sensitive, and it can often be difficult to get such a precise micro-adjustment with a screwdriver.


Collimation is often the most frustrating aspect for beginners, but it doesn’t have to be. Bob’s Knobs makes it easy to collimate your Newtonian or Catadioptric telescope with their collimation thumbscrew sets. There’s no screwdriver, no Allen wrench. Simply install the knobs and you are ready to collimate with the twist of a wrist. Bob’s Knobs work with many Catadioptric and Newtonian telescopes, from makers like Celestron, Meade, Orion, and more! Not sure where to start? The experts at High Point Scientific are ready to help you get the most out of your scope!

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