I didn't have any graph paper to draw out a template to make a fishtail splice, so I decided to make one on the computer. There's an allowance for band saw kerf at the point of each splice. Just print it out and use some spray adhesive to stick it to your billet. Make sure that you butt the top of the pattern to one billet and the bottom of the next to the end of the other billet. My pattern has an extra 1/4" at each end that I used to get the kerf allowance. Cut that off before affixing it to your billet.
Click here and select "download original" from the File menu. That'll get you the high-quality file.
Let me know what you think!