IF you really want to know how to build a QUAD than I suggest this site.
http://www.ecalc.ch/xcoptercalc.php?ecalc&lang=en
It costs $3.00 a month to access, but it will help you in evaluating your choices.
Here is a screen shot.
Here are the last 3 plates after rough cutting.
Here all 4 plates are loosely assembled to show the plan. The two major plates are 25 mm apart. You can see the prop arm. It is part of the Turnigy Talon, but shortened to 5 " . I am using their tube clamps to attach to the body plates.
There...
I have built and used a Turnigy Talon V2 frame and decided I could do better my self. I disliked the small center plates and I had to stack two more on top to get my electronics onboard. Then I needed to add protection or a cover. The landing gear are too short for an under mounted camera...