Double Fishtail Splice Template

Draw rectangular square 1" x 4"

Mark the center of the rectangle, top and bottom

Now divide into quarters, top and bottom

Draw a line from bottom left corner to top quarter mark

Now draw a line from top quarter mark to bottom center

Now draw a line from bottom center to top right quarter mark

Draw a line from top right quarter mark to bottom right corner. You will need two templates to complete the splice.