I used 5/16" hard wood dowel lengths which I cut to 1" dowels on the table saw set up with a 1" relief block. I placed each 1" dowel in my cordless drill and sanded the ends as they spin. By doing this the drill leaves 3 pressure marks on each end of the dowel which is great because it allows glue to squeeze around the sides of the dowel when you install them (Adding strength to the joint). I did find that the drill holes need to be incredibly precise to avoid dowels pushing the pieces out of alignment. If you look really closely, you might be able to see the alignment marks I used to ensure each piece was exactly where it is supposed to be.
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