A brazed joint between a cooling fluid box and an armature bar can comprise a cooling fluid box, a plurality of conductor strands, at least one side wall spacer, and at least one middle spacer. Each side wall spacer can have a tapered width and can be wedged between the plurality of conductor strands and an interior side wall of the cooling fluid box. Each middle spacer can have a tapered width and can be wedged between two columns of the conductor strands. The side wall spacers can taper in a direction opposite the taper of the middle spacers. In one embodiment, the cooling fluid box can move around the conductor strands. Each side wall spacer can be positioned against an interior surface of the cooling fluid box. Each middle spacer can be positioned between columns of conductor strands. The cooling fluid box can be withdrawn to a final position.