Quote:Hi, I want to put close to 800lbs of gear (mount, photographic newton,...) on a pier 13.5' above ground. Ground is hard clay. We live in southern France, there is close to no frost zone. I wonder if it would be better to dig a deep foundation, or a large foundation. Torsten
Scopes - 10" Meade LX200, Coronado 90mm, Vixen ED103, Orion 80mm Guide Mount - AP1600GTO Std (Encoders.... someday) Cameras - Atik 320E, Atik 314L+, Atik Titan, Mallincam Xtreme X2, Skyris 274M, Orion StarShooter, Canon 7D Instruments - L200 Spectrometer (300,600,1200 gratings), SA100 Diffraction Filters - LRGB,OIII,SII,Ha; J/C UV,B,V,Ic,Rc Way too many computers....
12.5 " F5.6 Homemade Dob , mirror ground and figured by myself 10 " F4.0 LXD55 Meade 6" F8 Homemade Dob , mirror ground and figured by myself , Sears 60mm x 900mm Refractor
Quote: I give advice for free, so I don't pay for any advice. Btw, I'm a professional astronomer, and I never had the idea of asking for payment... of any kind from amateur fellows...!
Quote:I won't ask Back Yard, he's asking for money for advice. No good
"The object in life is not to be on the side of the majority, but to escape finding oneself in the ranks of the insane." Marcus Aurelius (AD 121-180)
m1OASYS automation system
7x35 and 10x50 sears tower binocs, 3" f/10 edmunds reflector, 2.4" f/11.7 manon refractor, 6" f/8 jaegers refractor, 10" f/11 R30 Istar refractor, 3" f/15.8 sans&streiffe refractor, 3.1" f/15 selsi refractor(towa 339), 2.4" f/15 sears refractor, selsi 30x30mm spyglass, criterion 5-draw 25x45x75x spyglass(1957), 4.25" f/14.8 tasco 20te.http://cleardarksky.com/c/OmahaNEkey.html
CG5ASGT Astro-Tech AT6RC Zhumell 10 inch dob deluxe kit 10x12 observatory Echo Astronomy maker of Custom bahtinov masks and Duncan collimation masks.
Quote:I have the situation that my original slab is only 4" thick.I will therefore have to cut out the existing slab, dig in depth, etc....I did not know beforehands that I would one day construct a rooftop observatory at this place!
Quote:My 14' chimney block pier is attached directly to the garage floor pad. There's approximately 46,000 pounds of concrete in that pad. People walking around the garage during imaging sessions have had absolutely no effect on the telescope's performance. From my experience ... from the past 12 years of imaging using this pier ... I would not be concerned at all about placing a tall pier directly on a large concrete pad.
LX850 blog: www.LX-850.com
personal website: www.wadsworthobservatory.com
Quote:Maybe this is a stupid question, but won't you pretty much need an elevating pier if you use a roll-off roof? And, if so, is the movement precise enough to retain alignment on a go-to system?Evan
11" Edge HD Moonlite Crayford / Astro Tech 65Quad APO / on a CGEM-DX Mount / Under a TI Dome /EPs are TV 12mm Doles, Celestron 23mm Luminos, ES 14mm-20mm 100degree, ES 28mm-34mm 68degree,