This is the second mandolin that I have built.  I followed the instructions in The Ultimate Bluegrass Mandolin Construction Manual by Roger Siminoff except that I made an A-style instead of the F-style he demonstrates. The soundboard and bars are Englemann spruce and and rest of the instrument is made from black cherry except for the bridge and nut which are made from jatoba and the fretboard which is ironwood(hop-hornbeam). I carved the soundboard and back from 5/8″ thick plates to make the arched shape. The carving was all done following the instructions and templates in the book. The finish is Tru oil.