:) hi all looking for ideas on a different way of mounting my g70 currently i am using unistrut but the problem i have is that my pj is to low i am adding almost 6extra inches to to baseplate of my pj i know that unistrut is very strong and maybe the safest form of hanging 250lb from my ceiling but i have 8ft, ceiling and i would really like to reclaim some hight .I am using factory mount my pj faces south but my beams go east/west. thanks for now :)

There is a "low profile" factory type mount...that would only be about an inch or two in total height.

Are you using the factory mount AND a unistrut support system together?

One of the problems with the factory type mount is their small footprint and consequent lack of ability to bolt to two or more support beams....one method is to coach bolt a piece of structural ply to your supports, and then bolt the mount to that.....

How many support beans would be needed if one were to mount a g70 to the ceiling on the second floor. In other words it would be mounted to the jocyes (I think that is what they are called) that are part of the big roof rafter triangle (I know that's not what it is called :))

How many support beans would be needed if one were to mount a g70 to the ceiling on the second floor. In other words it would be mounted to the jocyes (I think that is what they are called) that are part of the big roof rafter triangle (I know that's not what it is called :))

A G70 weighs in around 80kgs (176lbs), and as such needs some structural reinforcement, as normally the projector is hung at mid span, centrally in the room. The ceiling joists job is to support the ceiling lining, and nothing else, economy of structure dictates the use of framing members that 'just' do the job. In Australia we have a timber framing code (AS1684) that details the selection and span tables of various timbers. Having said that, the average guy weighs more or less 80kgs, and your roof/ceiling can easily handle you walking around on or inside the ceiling frame. However one single ceiling joist WILL NOT support the whole weight, the strength is in the interconnectedness of the entire frame. You need a method of tying together at least 3 of the ceiling joists, essentially spreading (uniformly distributing) the load across, so each on carries a third of the overall 'dead load' of the projector.

From an builders perspective you should probably engage a structural engineer to check for adequacy in your given situation. However a large sheet of structural ply, screwed to the tops of your 3 ceiling joists would make for a stable platform to hang off. I don't want to make it more complicated than it sounds. A unistrut solution would probably be best of both worlds for you, if your not using a factory mount.

It's better to be safe than sorry when your sitting under 80kgs of glass and steel.

Those big "roof triangles" are called roof trusses :D

Thanks for the advise (and terms). I'm really not a total noob when it comes to construction, just a partial noob.
I actually live in a condo so I would probably have to check with the condo board since i would be attaching to the building structure.
With a unistrut solution would you still lay the ply on the top of the joists or would the unistrut serve to connect them?

Thanks for the advise (and terms). I'm really not a total noob when it comes to construction, just a partial noob.
I actually live in a condo so I would probably have to check with the condo board since i would be attaching to the building structure.
With a unistrut solution would you still lay the ply on the top of the joists or would the unistrut serve to connect them?

The latter.... :)