Wayne Parham Messages: 18791 Registered: January 2001
Illuminati (33rd Degree)
Some of my designs have ports made by drilling through a block of wood formed by panels layered on the baffle. Start with two or three small square panels of the same wood stock used for the cabinet, just large enough to cover the diameter required. Glue those to the baffle and drill through with a hole cutter. Any diameter port is easy to make this way, especially for relatively short ports that only need two or three panels glued to the baffle to get the desired length.