Does anyone know if the hole pattern around the primary is the same for a 1984 vintage C-11 as it is for a late 90s C-11? Ihave a newer C-11 OTA & am considering the purchase of an older fork-mount assy. but don't know if it wil "fit". Thanx!
C-11 screwhole patterns?
Started by choochoo, 10/25/2005 08:57PM
Posted 10/25/2005 08:57PM
Opening Post
Posted 11/05/2005 06:57PM
#1
The patterns are definitely different for the more recent Grey tube models like those used on the Nextstar series i.e. the NS11. The NS fork uses front-to-back side rails in leiu of the rear-hung arrangement of the old forks. People have drilled/tapped the rear cell to mount it in the older forks. I believe the '80s model Orange Tube C11's w/grey sandcast forks and '90s model Black Tube C11's w/Ultima forks share the same mounting hole pattern, thus the tubes and forks are interchangeable.
To verify my understanding I'd recommend you lookup the following Astromart sponser:
TELETRADE
http://www201.pair.com/resource/astro.html/teletrade/
email: [email protected]
To verify my understanding I'd recommend you lookup the following Astromart sponser:
TELETRADE
http://www201.pair.com/resource/astro.html/teletrade/
email: [email protected]
-Gary
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Posted 11/05/2005 11:51PM
#2
Hi,
If you go this route, be advised you will need 1/4x20 by 5/8" socket head set screws to mount the tube to the fork. Anything over 5/8" will hit the mirror. McMaster-Carr Supply Company has these, www.mcmaster.com
The setup also had a couple of very short 1/4x20 socket head screws inserted in the tube rear cell with just the heads sticking out that slid into slots inside the forks so you can let the tube hang there (pointed straight up) while inserting or removing the 5/8" long bolts. The threaded length on these was on the order of 1/4" or 3/8" max and they were towards the front of the tube from the holes for the longer mounting screws.
Dave
If you go this route, be advised you will need 1/4x20 by 5/8" socket head set screws to mount the tube to the fork. Anything over 5/8" will hit the mirror. McMaster-Carr Supply Company has these, www.mcmaster.com
The setup also had a couple of very short 1/4x20 socket head screws inserted in the tube rear cell with just the heads sticking out that slid into slots inside the forks so you can let the tube hang there (pointed straight up) while inserting or removing the 5/8" long bolts. The threaded length on these was on the order of 1/4" or 3/8" max and they were towards the front of the tube from the holes for the longer mounting screws.
Dave
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