Recently I added triangular knots across the top of this man's back, building on a backpiece begun last year. The central knot set the scale for the pattern, so the pieces now winging off to the sides were designed to accentuate the musculature and form a cohesive whole.
Expanded 'Awakening' Celtic Knot Tattoo by Pat Fish
Here is a link to the blog post for the center piece, done in 2015: http://www.luckyfish.com/blog/awakening-celtic-knot-tattoo