Roof top observatory question

I have been thinking about putting in an observatory on my roof for many years. (read: thinking about = waiting for wife's approval)

My question is, since a roof has a tenancy to become very hot during the day, does the heat radiating from the surface present problems with observing late in the night? Does it cause unwanted distortions is what I'm really asking...


Also, I've been thinking about the roll off roof design for a LONG time. I want to avoid putting supports at the opposite end where the roof would roll off. I've found one manufacture that makes industrial slides that can support over 1,000 pounds...but the problem is they are only 4 feet long. It is similar to a drawer slide. Has anyone seen or used such a part? They're a bit on the expensive side, so cost will most likely force me into putting supports in.

Anyways, thought I'd ask.


Thanks,

Phil Godfrey
St. Louis, MO

How about a design where the roof and rear wall roll off on rails that are on the slab, like a rail car?

By "slab" do you mean the other roof next to it?

I wanted to avoid putting any metal supports on the roof.

I like the drawer slide concept, that way it is not necessary to have supports protruding upward or metal track anywhere. It is self contained.

The only problem is I need about 9 feet of it. I could have it machined, it's a simple design but again cost will come to be an issue.

I was unable to locate the manufacture I found previously with the 4 foot tracks, but I did find this.

Attached Image:

How will you mount your telescope....(i.e., will your pier go to the ground?)

I have never seen a successful arrangement where somebody has mounted a pier to a roof (or deck), without sinking a pier all the way to the ground and isolating it from the roof (or deck). There are all sorts of creaks, shimmies, wind gusts, footsteps, and whatever that you would never think about that show up real well when you are using a telescope at 100 power.

That sweeping generalization includes several acaddemic settings (U of Redlands, top of the Ohio States Physics building) where people thought they were doing it right until it went into practice.

Alex

First question is your roof tile or shingle if shingle and heat is an issue you could apply elastrometric paint (white). For the track issue when I did my observatory roll off roof 12'x14' I used 1 1/8" angle welded to 3/16"x4" plate the wheels were 4"v casters all hardware welding material cost $875. Weight of roof 2900 lbs. As of today are temp. is 124 and with are dust storms (finer than flour) I have no problems with binding.