I was gifted this plane a number of years ago in a secret Santa gift exchange on a woodworking forum. I have used it a number of times, but not excessively. I went to use it today and it didn't want to take a thin shaving. I tried adjusting the depth of cut and it seemed that the blade was extending out the sole more than it should, but when I reduced that it wouldn't cut at all on a surface wider than the plane. When I took a cut on the edge of a 5/4 board (1" actual), It would cut just fine and remove a thin shaving, but the same adjustment wouldn't take a cut on wide surface. I took some photos of the plane. This plane has an adjustable mouth.
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I noted that the center portion of the plane sits slightly below the purple heart sides. You can sort of see the difference in this photo.
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So the question is, how do I fix this without messing up the plane?