[cabinetman]

Depending on your saw/blade/and you, you can get a pretty good edge with a saw cut. But invariably it won't be a surface that you can just apply a finish to. If you cut your frames, and they are the same width, stack them together on edge, clamp them, on a flat surface, and use a block sander. it won't take much, and you'll likely wind up with smooth square edges.

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