Advice on building a telescope

why? Your well aware of all the things that wont work tell me why they wont.

An "optical quality" paraboloid mirror is a very high precision object.
A shaving mirror is not paraboloid or hyperboloid or circular or "exact" in any conceivable way.
It doesn't have to be.
A paraboloid telescope mirror has to have a single exact focus point for parallel rays of light entering the front of the telescope.
You would never expect a shaving mirror to have anything remotely resembling a single "focus point".

ok thanks. Cleared that one one up.

Actually a shaving mirror will give a perfectly good image at unit power (i.e. x1 magnification) as can be demonstrated by casting the image created by the mirror on a white wall in a darkened room. On a bright day, turn off the lights and close the curtains so the room is dark. Open the curtains just enough to illuminate the mirror and move the mirror until the image comes to focus on the wall.

You could probably magnify the image a couple of times before the quality got too bad. Shaving mirrors are (very) roughly spherical and exhibit massive spherical aberration (the rays from the centre of the mirror come to a different focus to the rays from the edge.)

Phil.

Thanks. This may seem like a stupid thing to say and to may run foul of a few in here but bare with me Im new at this. But I had the idea just as a little experiment before I go buying mirrors and things to try and make a slap up scope with the magnifying side of shaving mirror and other bits and pieces to see what kind of results I get. Would this work or am I off my head.

Don't expect to get good views with that setup, you'd be very lucky to get a half decent image using magnifications used in binoculars.
Sounds like you need to do a fair bit of reading on telescope design and construction, the following is the bible for large Dobs,
www.bintel.com.au/Dobsonian_Book.html
I'd bet you could use alot of whats in there for a smaller scope.

the following is the bible for large Dobs

I'll second that. I have no DIY skills whatsoever & built a 12.5" dob mainly by reading that book. It's very well written.

By the way, I have a bunch of pics somewhere showing the construction process that I can dig out. If you want them just let me know & I'll send the to you. Probably better looking at that book first though.

Here is an article I found immensely useful. It doesn't cover the optical theory or balance (both covered in depth in that book) but it does show how he built his scope.

www.efalk.org/Miatascope/

Trev