Wallboard-fastening device for securing wallboards in an outside-corner configuration

A wallboard-fastening device for securing first and second wallboards to a framing member in an outside-corner configuration, comprising:

• first and second framing panels that directly connect to each other to form an inner corner seam that fits against a corner of the framing member;
• first and second tapered corner panels that directly connect to each other to form an outer corner seam and an outside angle that is greater than 270°;
• a first bridge panel that directly connects to (i) the first corner panel to form a first outer seam and (ii) the inner corner seam;
• a second bridge panel that directly connects to (i) the second corner panel to form a second outer seam and (ii) the inner corner seam;
• a first tapered flat-spring flange that directly connects to the first bridge panel such that the first flat-spring flange, the first bridge panel, and the first framing panel form a first channel sized to accept the first wallboard;
• and
• a second tapered flat-spring flange that directly connects to the second bridge panel such that the second flat-spring flange, the second bridge panel, and the second framing panel form a second channel sized to accept the second wallboard;
• wherein:
• the first flat-spring flange is configured to flex, when the first wallboard is inserted into the first channel, such that the first flat-spring flange pushes the first wallboard against the first framing panel;
• and
• the second flat-spring flange is configured to flex, when the second wallboard are inserted into the second channel, such that the second flat-spring flange pushes the second wallboard against the second framing panel.