Originally Posted by jmbtexas4
Is it easier to build these LED's with trim or zero edge? Does the frame need a gap from the wall in both situations, or can the trim serve as your gap?
On a 120-130" screen, what is the ideal distance between the LED and the wall? In the example above with the LED on the back of the 1 x 2 facing the wall, we are talking roughly 3 inches right?
Myself, I would design in no less than 1", but no more than 3.5"
That is why I almost always use 1x3. The 1x3 is only 2.5" tall on edge...and that is a good distance that helps diffuse the intensity of the LEDs, reducing "wall shine".
Making sure there is enough depth from the leading outside edge is also important. The two, depth to edge and depth to wall both work together to create a glow...not a overly coherent "beam"
If you had to build a Frame "Flat", I would use 2x Lumber such as 2x3, but such a Frame would out of hand require Trim anyway, such a 1/2" x 2.5" or 3.5" Velvet Wrapped Base.
Now one thing that can help mitigate some of the brightness issues is to chose LEDs that are dim-able.
You still want some depth to the outside edge, but Frame depth can be reduced, so that you could go Flat.
But again...a Flat build presents a broader contact to whatever material is being used, and that is why a raised perimeter is so essential. Also, any Vertical Bracing really doesn't add much as far as helping prevent "Frame Twist" from corner to corner, so you must really work harder to attach such a frame on all four corners against the Wall surface. French Cleating is not an easy option under that circumstance.
A "on Edge" build is very much more rigid and can be more easily build to be "square" diagonally, and "plumb" as far as being Flat.
On edge is the way to go, and creating a right angled "L" type edge the best way to engineer in the needed overlap.
The final choice being yours, and frankly, unless you understand every aspect of such a build, it's best to strictly follow the directions given...to a "T", using the recommended materials and tools.
To provide that for you in diagram form, all that is needed is a set of the exact, desired Screen size dimensions.