An assembly of mechanical components includes a solder joint between two metal components. A mounted component is retained on one side of a support structure by a solder joint on the other side of the support structure between a retainer and a connector that is fast with the mounted component and extends through the support structure. The retainer is of sheet metal construction, so that a height of the solder joint is no more than the thickness of the retainer, thus providing a low-profile joint. The assembly may be in the form of a movable push button for control of an electronic device.