Well ------------------I haven’t done anything “Original” in quite awhile, so I thought I would throw this out as a topic and thread. I have done a few "Quads lately and have formed an “opinion” about fin placement and any bump that may be incorporated into the overall outline or template. I have come to the conclusion that the “bump” or "wing " should be at the rear of each fin on each side of the overall template. It took a little effort and counseling from my glasser to come up with the proper fin placement even for a “Quad” with no "bumps’ or “wings”. Wide Square-tail, Swallow-tail or Fish-tail, makes no differance on the overall tail shape. If you are going to incorpate “Bumps” or “Wings” it seems to me that the “Wings” have to be placed at the rear of the fins to make sense. Right or wrong? Your opinions please?
what? No opion? Too technical?
McDing, I agree with you at the moment like the pic of a Black Knight below, but just retro fitted a board with the wing in the middle of the rear set-up of the quad fins. I think any part from the thickest part of the foil of the fin to the trailing edge of the fin is a safe area to work with the wing on the rail . Mahalo,Larry
McDing, Here’s a Board John Belik did, notice the back of the front box is even with the wing, but when the fin is put in, the wing lines up with the middle of the trailing edge foil on the fin.
Mahalo,Larry
McDing, Here’s a KG board.
BEFORE
AFTER
Mahalo, Larry
all summer I’ve been building & riding really short wide quads, 5’2 to 5’4 range. a gnarly set of wings lets me go as wide as I want but still keep the top secret formula for fin cluster placement on magic little things like these
bottom line, I’m sooo stoked on how well they work
Nice Board Bud, I like the wings for that same reason to go wide.
McDing after seeing Bud’s board, answers another good question " Is there a formula with fin placement and wings on a Quad?" I would say No, but cluster placement is important.
I know how wings work on my favorite double winger single fin, but still playing with Quads for the pass 2 years.
Mahalo,Larry
Most of the time, they’re placed at the trailing edge of the fins, and that makes sense to me, but I’ve also seen them at the leading edge of the fins. I’ve never ridden them (on quads) so I don’t know how they work.
As I understand it, and in rough, general terms, the bump serves to shorten the rail line and reduces wetted surface in the tail. Moving the bump up to the leading edge shortens the rail line considerably and reduces the curve in the outline behind the bump. So if your planshape starts with a really wide tail, it makes a straighter rail line through the middle and back to the bump. The bump then reduces the tail area along the fin and back to the pod, removing more surface area then if the bump were at the trailing edge.
Bumps at the trailing edge of the fin makes the rail line longer, and maintains more curve in the planshape.
I would like to see an asymmetrical board with a bump on the heel side at the leading edge, and at the trailing edge on the toe side. This might work well on flatter, wider, fishy type boards that many say have problems backside.
Great! Thanks guys. This is what I was looking for. Theory, opinion and proven fact.
Bud----------Nice shapes. The "diamond-tail seems to blend well with the wings.
I would like to see an asymmetrical board with a bump on the heel side at the leading edge, and at the trailing edge on the toe side. This might work well on flatter, wider, fishy type boards that many say have problems backside.
Hey NJ_
Good theory. Makes sense to add a little help to the backside rail since heel pressure isn’t as agile and adjustable as toes.
Shape one up!
~Brian