110" 16:9 Screen
The screen you use for front projection can make or break your home theater. There are lots of very nice screens available from commercial companies, but often they are pretty expensive. This 110" screen costs less than $100 in materials to make and I've been very pleased with the results. This screen follows the same design as one of my previous screens with a few modifications because of it's size. I, like many DIYers, buy the vast majority of my materials from Home Depot and the largest size they sell 1/4" plywood in is 8'x4'. This is fine as long as your screen doesn't exceed 4' of height (since I use a 3.5" border the largest viewable height you could use with this design is 41"), but if it does then you'll have to use multiple pieces of plywood. For my first 16:9 screen the viewable height was 36" (64" wide, 73" diagonal) so it was no problem, even with the 3.5" border. This 110" widescreen required a viewable height of 54" and a viewable width of 96". I eventually settled on a design that used 3 pieces of 34"x60" 1/4" thick plywood (Home Depot also carries a 4'x8' sheet of something called Verona that can be used). As is the case with my previous 73" widescreen I chose to paint this screen with the much discussed Misty Evening color using an HVLP sprayer (Campbell Hausfeld HV1000).
Construction:
As you can see from the diagram the screen is made up of 3 different layers. First there is the border which is made of 1"x4" slats. These are fixed together using 2" 90 degree brackets (Home Depot internet/catalog #805030) on the inside corners and flat 2" mending plate (from Home Depot as well, though not on their website) where the slats meet on the outer edges. These will create the 3.5" boarder around the screen. Once this boarder is constructed I bought a large sheet of black felt (Walmart) measuring 64"x9'. I laid the border down on top of the black felt and then trimmed and stapled the outside edges using a pair of scissors and a staple gun. This procedure is very similar to the way I created the masking for the screen, please see that article for pictures detailing it. After the felt was stapled on the outside I cut a small piece of cardboard 2" wide and of arbitrary length and used it as a guide for marking the inside fabric, sliding it around the edges of the border. I then cut along the markings leaving me with 2" of fabric along the inside of the border and then cut the inside corners at a 45 degree angle. Now I folded the inside fabric over the border and stapled it tightly in place. Once all the fabric was stapled I went around the edges with a hammer tapping the staples all the way flush with the fabric and wood. Additionally, you may wish to go over the exposed metal 90 degree brackets on the inside corners with some black paint. The border was finished. If you are building a screen that doesn't require more than one piece of plywood to be bonded together then there is no need for the third layer. Also you can paint the plywood by itself and then screw the border into place after you're done. This will avoid some time consuming masking.
The second layer is 1/4" thick plywood. You should take this opportunity to thoroughly sand the faces of all three pieces with a low (about 80 grit), medium (about 120 grit), and fine grit (about 240 grit) sandpaper.The border was placed face down and all three 34"x60" pieces were placed on it, flush with each other, leaving a 1/2" gap around the three pieces (103 - (34+34+34) = 1) (61 - 60 = 1). They were then carefully screwed into place around the edges of the border.
The third layer is 4 60" 1"x4" slats. The slats were laid on top of the plywood (assuming the screen is still face down), two over the far edges and the other two covering the seems where the three pieces of plywood meet. The slats were then screwed into place along the border (careful to remember that you cannot screw the two middle slats into place anywhere except at the top and bottom, this would result in screws coming through the face of the screen).
Once all the pieces of the screen are secured you can flip the screen over so that it is face up. At the point I took a 2" wide roll of 3M blue painters tape and masked off the cloth of the border. It is very important that you take your time while doing this to ensure the fullest possible coverage. After that is done I put a piece of drywall tape down each of the two seems and proceeded to spackle them using some vinyl spackling. It may take several coats of spackling to get good coverage. Once the seems are fully covered you should sand them using low grit sandpaper (electric sander works just as well as by hand) until the seems are flush with the rest of the plywood. This is difficult and a perfect result cannot be achieved, try to get as close as possible, but when a picture is being projected the imperfections won't be noticeable. After that go over the seems with both medium and fine grit sandpaper. Next is the fun part.
The time has arrived to prime and paint. For those of you who do not already own an HVLP sprayer (heh, I didn't before I got big into DIY) you may opt to roll on the paint. This is a perfectly viable option and will yield results that are, for the most part, indistinguishable from a sprayed screen. I use a sprayer because it is faster and makes for easier cleanup as well as giving a smoother finish. I would prime with at least 2 coats of Kilz 2 (latex) allowing for an hour of dry time between coats. After the last coat has dried I recommend you sand with medium and then fine grit paper (again, electric is fine as well as hand). You should now have a very smooth white finish through which upon close inspection you can see some wood grain from the plywood. If you're using a CRT projector or don't want to go after the added benefits of improved contrast with Misty Evening you could stop right here and have a perfectly good screen. If you want to continue then paint with 2 to 3 light coats of Misty Evening waiting at least an hour between coats. Once your last coat is dry you should sand with medium and fine grit paper. If sanding reveals the primer in some spots then you should do another coat of Misty Evening. Once you're finished you should have a very smooth light green finish through which upon close inspection you can see some wood grain from the plywood. Each time you sand a significant amount of dust should accumulate. Remove it as you see fit. Once it's gone you can remove the tape mask and you should be left with a very nice screen. Below is a picture that shows my original 73" screen placed in front of my newly build 110" screen and gives you an idea for the difference in surface area.
Mounting:
This part is always pretty interesting. There are a lot of different ways to mount a screen, this is just the way I did it. I used the same technique to hang both my 73" screen and my 110" screen. I estimate the 73" screen to weight approximately 15 pounds and the 110" screen to weight approximately 50 pounds. I mounted a ring hangers (Home Depot internet/catalog #908850) in each of the upper corners of the 73" screen and a ring hanger on the top of each of the 4 support slats for the 110" screen. Once the ring hangers were in place I sunk 4 drywall anchors (for the 110" screen, 2 for the 73") into the wall at my desired height (top of the 110" screen is about 6" from the ceiling). It is critical that you spend a lot of time making sure that the drywall anchors are spaced the correct distance from one another and also that they are all level. If you make a mistake here you may be able to move one of the ring hangers to accommodate the miscalculation, but if it is too far off you will have to move the drywall anchors. I cannot stress how important it is to get this right the first time. Mounting is difficult to do by yourself, I highly recommend help from a friend or two. Once the anchors are in the correct places the screen should be lifted up into place and hung on the drywall anchors. Once the screen is hung you may notice that it is closer to the wall at the top of the screen than it is at the bottom or vica versa. This can be corrected by remove the screen and adjusting the how far the mounting screws are sunk into the drywall anchors.
