How many studs is enough?
Hello! I am trying to mount a 72"x12" shelf using 5 L-shaped mounts. The studs do not line-up with my shelf and I cannot move the shelf in either direction (door frame on one side, bookshelf on the other). I do not want to have off-centered mounts for the whole shelf and was wondering how many studs is enough. I can hit two studs on the right side of the shelf, but the middle and left two mounts would be toggle-anchors. Is that enough to hold the shelf? I would like the shelf to hold 40-50lbs on it, but the weight will be toward the front edge of the shelf (it will have large Lego sets on it). Would two studs be enough? I can put the "middle" bracket on a stud as well, but it won't be centered. Would that make enough of a difference to warrant off-setting the middle mount and having the left side mounts a little more "compact".
The spacing with two studs would be 6" overhang on either side of the far brackets, with 16" spacing between the two outer brackets, and 14" spacing between the middle and inner brackets. The spacing with three studs would be 6" overhang on either side of the far brackets, with 16" spacing between the right three brackets, and 14" spacing between the remaining two brackets on the left side. I know this isn't a huge difference and isn't terribly noticeable, but I'd really like to have evenly spaced brackets. But, if that "middle" bracket being on the stud is a huge deal, then so be it. It must be done. Thanks in advance.