Welcome to spira international home-built boat plans. if you’ve ever wanted to build your own boat, wood, aluminum, or stitch-and-glue,. Larger stitch & glue boats: 12′ bahia mini panga 16′ robalo junior panga 18′ veracruz panga 19′ quintana wide panga 21′ tiburon panga follow spira boats on:. See our panga boat plans to learn more about this plywood boat construction. panga 20 – study plans: specifications: as all our stitch and glue boats,.