Posted 27 June 2013 - 05:12 PM
Posted 27 June 2013 - 07:19 PM
Posted 27 June 2013 - 08:38 PM
As well as provide a "cut to the chase" grouping. I'm not really sure which of the "numbers" you mean, and thus which you need help with, although I would suspect it may be the properties of your mirror substrate (Modulus of Elasticity) as well as "what is good enough"
Posted 27 June 2013 - 09:07 PM
These articles show a simple plywood cell that has worked for me:
I used three generous blobs of silicone caulk to fix the mirrors to the finished cells.
Posted 27 June 2013 - 09:22 PM
Posted 27 June 2013 - 09:23 PM
Posted 27 June 2013 - 10:04 PM
Posted 27 June 2013 - 10:09 PM
Posted 27 June 2013 - 10:27 PM
Posted 28 June 2013 - 07:00 AM
I am building a 8" f/5 truss dobsonian. My goal is to be able to make it as transportable as possible.
so you don't have to glue it, you can sit it on bubble wrap as your float support, just cut a central hole about 2.5" in dia. [our friend Reiner [mr. lowrider] has this on his travel dob]
you can use a top plate of the mirror box as a edge support.
you can "hang" the mirror cell from that same top plate so you'd have front collimation bolts - they are priceless.
then you can use swing away clips for transporting.
on an 8" you can make your own truss clamps. just make sure the thumb part of the thumb screw faces the mirror side on the mirror box, opposite the vid.
Posted 28 June 2013 - 10:04 PM
Posted 29 June 2013 - 12:58 AM