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Tomorrow begins 8" refractor build officially

Started by Greg Shaffer, 12/20/2014 10:55AM
Posted 12/20/2014 10:55AM Opening Post
Finally moving ahead with my 8" (7.75"clear aperture x BFL 123 3/8") which translates out to F/15.919 and tomorrow a friend and I are going to build the mockup to determine the exact 9" tube length....using 4 pcs of 1"x10' aluminum tubing, a leather belt around the cell, some motorcycle tiedowns, duct tape and a pc of 10x10 plywood with holes for the tubes in the corners and the focuser mounted in the middle and a couple more tiedowns on the other end.....rough aligned with a laser and then propped up to look in the sky if the clouds co-operate....find infinity focus and take some measurements so I can order the tube from from hastings irrigation. Plan is to account for using binoviewers without OCS or barlow and then use focuser extensions when single EP viewing.

My friend is also a machinist and is making the backing plate and adapting the cell to the tube....

20" MidnighTelescopes f/5
8" f/16 Muffoletto Achro
Meade 6" AR6 f/8.0 Achro
Celestron C11
Parallax PI250 10" F/5 Newt
Vixen FL102S,NA140SS,R200SS
80mm Stellarvue Nighthawk with WO APOupgrade lens, 90mm f/16.67 Parallax Achro
LXD75/LX200, Mini-tower, GP-DX, CG5 ASGT, LXD650, GM-8, G11, GM-100, GM-150EX, GM-200 and a Gemini G40
4" portable AP convertable 44" or 70" pier
Stellarvue M7 Alt-Az, TSL7 Pier/Tripod
12.5" f/5 MidnighTelescopes DOB Swayze optics
Statham GA
Posted 12/21/2014 06:04AM #1
This sounds like a fun build....keep us posted!

I have a 6" f15 TMB doublet that I plan to build with the same Binoviewer/Monoview goals in mind. I was thinking of constructing a square plywood tube for the prototype build to verify the precise length I need from Hastings. I need to find a machinist for the countercell and focuser back plate.

I'm interested in any lessons learned!

-Gary
    There is only one constant in our infinite universe; it is change.
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