Quote:
Originally Posted by dave brock
Hi Simon.
You haven't said what make/model scope it is so I can't google to see the set up but I'm not sure why you need to drill 8 more holes. Are there no adjustments at all to move the secondary back? If you turn the spider 180° won't at least 4 of the holes still line up? I'd have thought though that there would be enough flex in the vanes to reuse the existing holes. They may just no longer be exactly 90° anymore.
Dave
|
Hi Dave, thanks for the reply. The scope is an ATM job(not by me), and done rather well with the exception of the misplaced spider.
The primary-secondary offset is correct, approx. 5mm toward the primary, so it doesn't need moving back.
Sadly no, none of the holes will line up with the spider when rotated 180 degree's.
The spider is by Protostar
http://www.fpi-protostar.com/s4vmnts.htm, and to effect the offset, two vanes are ~65mm long and two are ~60mm long. See quick CAD sketch below.
I would prefer to keep the vanes at 90deg with relation to each other.
I have marked the hole locations on the tube, about to start drilling
EDIT: Updated sketch, black spider is current position, magenta coloured dashed spider is where it needs to be.