I decided to build my first DIY projector mount, and designed around an idea I saw here, but using plexiglas instead of the typical plywood. Here is the process I took:
Here is the bottom (ultimately the top) of my BenQ PE7700 projector that I have to work with.http://www.miltech.org/photos/AVS/mount/BenQ_Bottom.JPG
The holes are M6 metric threads, so I bought four 1" screws to mount the first layer of plexiglas to the PJ. I used 1/2" nylon spacers between the plexiglas and PJ to keep it straight -- it also rested on the legs which was convenient. The four long bolts (4" x 1/4") are used to attach to a second tier of plexiglas which is ultimately connected to a pipe.http://www.miltech.org/photos/AVS/mount/BenQ_Mount1.JPG
I bought 1.5" galvanized pipe (12" long in my case) from HD, and two flanges, screwed them together, and painted them white for WAF. I also painted the screw heads for the lag screws that will be used to attach the flange to the joist.http://www.miltech.org/photos/AVS/mo...Mount_Pipe.JPG
Here is the finished product. I used wing nuts for easy adjustment, and it was very easy to fine-tune that way. I initially drilled slots for the attachment of plexiglas to flange and used wingnuts, in case I needed to twist the entire PJ around its vertical center, but it turns out that the actual pipe is at a happy-medium of resistance where I can just twist it to where it needs to be and it holds in place. We'll see how that works long term.
Also, I ended up being right on a joist, so I just used two lag screws (2.5" x 1/4") into the one joist, instead of all four.http://www.miltech.org/photos/AVS/mo...Y_PJ_Mount.JPG
If I hadn't been able to mount straight to a joist, or wouldn't have minded spending more time on it, I would've drilled a hole in the ceiling directly above the pipe, and a hole in the upper plexiglas tier to run cables through. I'll do it it that way when I build my dedicated HT.
I thought this may give others ideas regarding DIY mounts...
Oh, total materials cost was around $25 + plexiglas (I was able to get some for free) + spray paint.