I have a projector screen (45lbs) that I have to hang on the ceiling on it's two ends. However the joists on the two ends are not correctly positioned so I can't hang the projector screen where I want to hang it. So I went to the attic and found that there are two joists spaced 3 feet apart. The point where I want to hang the projector screen falls between the two joists. So I bought a 2x4 stud wood and now I want to connect that wood between two joists. However I don't have access to the side of the joists. I want to see if there are any flat metal connectors or something like that I can use to connect the joists using the stud wood. What's your recommendation?