There are a few ways to mount the motor. The 8″ bandsaw I built earlier this year just sat on the box base and moved left-to-right in mitre slides for belt tension, and front-to-back for V-belt alignment.
The original 14″ bandsaw I built in 2014 used a hinged motor mount with threaded rod for belt tension and mitre slides for V-belt alignment.

Decided to go with a hinged motor mount, the weight of the motor (quiet heavy) will assist with V-belt tension.

The motor assembly also needs to move or slide front-to-back to allow for belt alignment.

More to come…