I'm looking to install some floating shelves (I originally wrote "cabinets", sorry) in my apartment and want to put some moderately heavy things on them (likely under 100 pounds over a 48 inch long span).
I'm 95% sure there are metal studs and I can reasonably identify their location (though not necessarily their center) via my magnetic stud finder.
My only real question is how would I know which length toggle bolt to purchase?
I know I'd need 1/4 inch width bolts but I'm uncertain on the optimal length (presumably 3 or 4 inch)
Also, if the shelving bracket has 3 holes
should I use three toggle bolts per bracket or is that overkill (or perhaps would just weaken the drywall/stud?)?