I decided to post a thread on this for others to use. I built a horizontal masking system for my 106" fixed frame screen. First of all the screen frame is an Elunevision frame. I switched the Elunevision fabric to Center Stage XD material. You can see the thread here: www.avsforum.com/avs-vb/showthread.php?t=1180610&highlight=convert+elunevision
My masking system consists of the following items:
1. 7 ply fiberglass faced plywood. (Had this at the shop so I used it)
2. Two pieces of flat stock sheet metal. (Had this at the shop. I think it is 24gauge.)
3. Flat stock of sheet metal. (Had this at the shop. I think it is 28 gauge.)
4. 12' of 1/16" air craft cable. TSC
5. Triple black velvet. SY Fabrics
6. Small turnbuckles for cable length adjustment. TSC
7. Four 1/16" cable clamps. TSC
8. Two oval chain links to connect turnbuckles to masking system. TSC
9. Two screw hooks to hang pulleys. TSC
10. Four heavy duty draw slides. Lowes www.lowes.com/lowes/lkn?action=productDetail&productId=50184-130-8400PR 18&lpage=none
11. Two pieces of 12" long 1/2"x1/2" aluminum angle. (Had this at the shop.)
12. Sheet metal screws, wood screws, wood glue and 3M Super 77 spray adhesive. (Had these materials at the shop.)
I made four sheet metal angles (24 gauge) 3/4"x2"x8" long for brackets. These were fastened vertically to the back of the screen frame, about 1-1/4" in from the outside edge of the screen frame. I attached the draw slides to these brackets. I made four sheet metal (28 gauge) U-brackets to wrap around the end of the screen frame. These brackets have a 3/4" leg coming off of the "U" so that I could connect the other half of the draw slide the the "U" bracket. The "U"-brackets are 6" long and the legs are 3" (face) 2-3/8" (side) 1-1/4" (return at back) and 3/4" leg to attach to draw slide. With the brackets and draw slides in place I now have four pieces of flat sheet metal (face of "U"-bracket 6" high x 3" wide) in front of my screen frame to attach the masking panels. These brackets are free to move (18" total) up and down the vertical face of my screen frame.
For the masking panels I cut three 8" wide strips from the plywood. The third strip is need so that I can make two panels 98-3/8" long. I beveled the top edge so that when the panels are in place there is a slope on the edge towards the screen. I used wood glue and biscuit joints to make the panels the length I needed. Next I simply covered the panels with Triple Black Velvet.
Since the distance from the back of the masking panel to my screen is about 1-1/4" I needed a way to extend the masking back to the screen. For this I made two sheet metal angles (24 gauge) 91-1/2" long with 1-1/8" leg and a 2" leg. inside to inside of my screen frame is 91-3/4" so I have 1/8" clearance on each side. These sheet metal angles serve two purposes. One is to extend the masking to the screen and the other is to keep the masking panels from ever bowing. Angle is attached to the masking panel every 10" with wood screws. The angle sticks up above the masking panel 1/8".
To cover the angles I cut two strips of velvet 4" wide and 94" long. I sandwiched the velvet between the masking panel and the sheet metal angle. The ends of the velvet were folded back and tucked under the ends of the angle. This created an edge that extended about 3/16" past the end of the angle. This was done to fill the 1/8" gap between the masking and the inside edge of my frame. I then sprayed the inside of the angle with Super 77 and wrapped the velvet around the angle.
I removed the sheet metal "U"-brackets from the screen. They slide off when you press a release button on the draw slide. I then screwed the brackets to the back (end) of the masking panels. Then I simply slid the brackets back onto the draw slides. With the masking panels fully open (1.78) the 91-1/2" long sheet metal angle rests against the inside edge of my screen.
The cable system is very simple and used by others here. I attached the 12" long x 1/2" x 1/2" aluminum angles to the back of the "U"-brackets on the top mask so that I would have a cable attachment point six inches below the masking panel. This allowed me to mount the two pulleys lower so that they are behind the screen rather than above the screen. I installed the two pulleys so that the top of the pulley is about 1-1/2" below the top of the screen. I connected a turnbuckle to the bottom mask and ran the cable up to the pulley and then down to the bottom of the 1/2" x 1/2" aluminum angle connected to the "U"-bracket. I did the same on the other side. I adjusted the turnbuckles so that the masking when fully open has the 91-1/2" sheet metal angle resting against the inside edge of my screen. Now when one panel is moved the other panel moves the same amount in the opposite direction.
I did not take pictures during the install, but here are pictures of the masking panels in place.
1.78 screen aspect ratio
2.40 screen aspect ratio
Close up of the masking panel. You can see the slope on the plywood edge and it shows the angle raised up 1/8" above the edge of the plywood masking panel.
Pictures were taken using hand held camera and flash. That is why you can see the aluminum driver of the sub. Very pleased with the results. It seems to be a lot more emersive when watching movies with out the gray bars. The hardware cost me $24.00 from TSC. The Velvet $29.50 from SY Fabrics and the drawer slides $24.00 from Lowe's. Since I had all of the other materials the total cost was $77.50.