i am making a 6-0 fish right now and i want to make it single fin. the crack is about 6.5" deep and how far from the crack should i put the fin box. what size fin should i use? any suggestions
Id suggest putting the fin box as far back as the thickness of your tail will allow. The depth of the crack of your swallow limits how far back you can position your fin box. From my experiences, most fin boxes are 5-5 1/2" from the tail, so yours will be at least 7" or so. That might be a disadvantage if you need or want to move the fin back.