These instructions are for a Hitachi Dukane projector, but could be easily modified to fit any other projector.
Hitachi Dukane projector (model #: CP-X345)
Aluminum strip (3/4" x 1/8" x 48")
Galvanized Steel 6" Nipple (1/2" x 6")
2 1/2" Galvanized Iron Floor Flange
4 4mm Flat Washers
3 4mm-.7 x 25mm Machine Screws
2 1/2" Nylon Spacers (3/8" OD x .171" ID)
2 4mm-.7 Hex Nuts
3 #10-24 x 3/4" Flat Head Machine Screws (matching nuts should come with these)
Flat Black Spray Paint
Drill (with various bits)
Flat Metal File
Step 1: Getting Started
Step 2: Drilling Second Hole
Drill a hole on the spot you marked. Draw a line on the aluminum, about 1/2" from the hole you drilled. Use the saw to cut the strip along the line (this is where the vice comes in handy).
Step 3: Attaching the Flange
Place the flange on top of the aluminum strip so that the flange is centered on the projector and the aluminum strip is visible through two of the flange's holes. Then, mark the aluminum strip at the center of the two holes. Drill a hole through each of these two marks.
Detach the strip from the projector. Place two #10 screws through the flange holes and their corresponding the holes on the strip. Tighten a nut onto each screw.
Step 4: Drilling the Third Hole
Use the #10 screw as a pivot to mark where to drill the third hole, similar to Step 2. Drill the third hole as marked.
Draw a line on the aluminum strip about 1/2" from this third hole. Use the saw to cut along this line.
Step 5: Shaping and Painting
Use steel wool to brush the surfaces of the two aluminum pieces, the galvanized nipple, and the floor flanges. Spray each of these parts with several (3-5) light coats of black paint.
Step 6: Assembly
Place two screws with washers through the first two screw holes with a nylon spacer on each.
Put the third screw through the aluminum, then through a 4mm hex nut, then into the projector. This nut can be used to adjust the tilt of the projector once it's on the ceiling.
Screw the nipple onto the flange.
Attach the remaining flange to the ceiling.
Finally, place the threads of the 6" nipple into the ceiling flange, and rotate the entire assembly to screw it in.