both the size, strength of the magnet, and permittivity of the material you are holding will decide the maximum weight. If we are talking about sticking to steel then I would guess the biggest strongest one would hold 15 pounds. The weakest ones would hold 5 pounds.
Select as Best AnswerUndo Best Answer
I have several - as others say its dependent on the strength (high power since its for an hdd) and what its stuck to/how much surface area. Magnetic flux is strongest closest (inverse square of the distance), so the more surface area, and closer you can get the object, the better it'll stick. I'm just guessing, but I'd say mine could easily hold anywhere from 30-100 pounds if applied well and the load is level (doesnt pull the magnet off at an angle). When I get home there will be some measuring.
It depends on the dimensions of the magnet (among other things). Post the measurements of it and one of us can tack a crack at estimating its pull.