Thor hammer If you want to use it with a magnet, it will be necessary to add it before the end of layer 21 because the magnet is hidden, this in the case that it is printed with a layer height of 0.2 mm, the maximum dimensions for the magnet are width 7 mm x height 3.5 mm x length 3.5 mm. The dimensions of the hammer are height 128 mm x width 122.8 mm x length 37.5 mm.