I designed a simple wall mount for my LG PH550G projector. It is angled at 10º and allows projecting the image on the ceiling, so that I can watch movies while lying on the bed. It’s a setup that I always wanted to try, because it seems to be the most comfortable way of watching movies while lying down, since the image is projected directly in front of you. Without a projector, this could only be achieved by hanging the TV on the ceiling, but that’s awfully complicated and somewhat unsafe. Normally people just put the TV in a high mount and bend their necks at uncomfortable angles.
This support is composed of two parts joined by a double T-slot that firmly supports the weight of the projector. It allows fast removal, in case the projector is needed somewhere else, e.g. for a presentation. In case a different angle or projector model is to be used, only one part of the support needs to be printed again, while the part linked to the wall may remain the same.
I have also designed a very simple cover for the projector lens, since it is much more susceptible to damage and collecting dust when it is pointed upwards. The support files are available at Thingiverse: Projector mount at 10º angle for LG PH550G
I am very satisfied with the video setup, the PH550G has USB, HDMI, VGA inputs and 3.5 mm audio output, which allow me to watch movies stored in a thumb drive with headphones. Those connections alone already make the setup pretty useful, but it also has Bluetooth and Wi-Fi Direct, so that I can use a wireless speaker or headphones and mirror the screen of a PC or cellphone. It has an internal battery, allowing it to be used for movies or presentations anywhere. The included remote control enables presenting and controlling media playback without the need of a computer.
Another great feature, that I didn’t expect when I bought it, is the automatic keystone correction. The projector detects and corrects the image tilt and rotation, making it very easy to setup anywhere, without looking for keystone configurations on the menus (manual adjustment is also available). As far as I tested, the image is adjusted to the closest 90º angle, so you can point it at a wall, floor or ceiling and is automatically corrects the keystone, in order to achieve a proper rectangular image.
Just as a footnote, this mount design was the second one I tried, before succeeding. The first one was a simple hinge that would allow me to rotate the projector 90º, therefore projecting on the ceiling or on the wall. It turns out that the projector is too heavy to be supported by the hinge without an additional angle control mechanism. Controlling the angle would have been possible by a mechanism like the ones used in telescope supports (used for star tracking), but it is much more complicated and would have taken a lot of effort to design it in a 3d-printable way. Since I only intend to use the projector pointed at the ceiling, it made sense to have a fixed angle with a very sturdy support that might be easily exchanged. The pictures below show the first iteration of this design.