Hard tuck VS. soft tuck in the tail

I generally know the differences of tucking the edge along the rail, but haven’t found much info for tails.Should the tuck generally be 45 DEG. from the rail appex or should the edge be tucked under a little in the tail? This would be for tri and quad shortboards ,not single fins. Sorry if this a been covered before.Any advice or links would be great. Thanks!

hydrodynamically I have no clue - I round the rail over so the bottom half is tapering in, but stop short of actually rounding it at the bottom corner.  Still leaves a nice square edge in the tail, but blends better visually with the rounded rail further up.  Not so critical on a pintail where the tail is tapering rapidly anyway, but on a board with a wider tail, the transition from round rail to square corner at the bottom can look funky.  Kensurf taught me that (I should say, he posted that once, and I took note), and since he did, I can notice from a block away when its not done that way.  I also think thats how most of the pro-shaped boards I've seen are done.

I describe it this way… if you look at the bottom of the board, starting at the tail, the edge should be untucked, hard and square at the tailblock. As you you slide your hand and eye forward, the edge begins to tuck, and the rail begins to get some curve… begins to round. As you move forward of the fins, the edge rolls over onto the bottom of the board as the rail begins to really get round… look more like a rail. About 12" forward of the fins, the rail continues to tuck under and soften, blending into the bottom to form a soft, blended rail radius. There is no “transition.” It’s a continuous rolling under (tucking) then softening.

You can run the tuck all the way through the tail, doesn’t have to be squared up and hard. Just keep some kind of edge. Different shapers like to have the squared off tail, but I’ve seen tucked under all the way, and I have seen hard down rails like what Hynson does.

Think of the tucked under edge as cutting off a piece of the bottom of a circle. The rail is circular with a diameter that goes from small to larger back to small. The ratio of the cut should be consistent.

Someone has posted graphics so you should be able to find something then just use that as your guide. I personally like a tucked under edge almost all the way through. I also like a thinner rail diameter on those.