Where do you place twin keel fins on a board setup for quad fins. Do they always go in the most forward boxes or sometimes in the rear boxes?
If the tail of the board is wide enough, you can try in the rear, to ride them a bit like a Simmons:
The board will become stiffer, with more latency going into turns, but by putting your rear foot well on the tail, you may enjoy a different kind of ride: More like banking into smooth turns as with an airplane, rather than a skate where you can break the trajectories at will anytime.
I had a Simmons-like SUP with 4 boxes, and I did not like the keels in front: the board was entering the turn immediately, so I did not have time to properly set up and dig the rail to really carve the turns, it kind of "dishpanned" by itself. With the keels really on the tail end, the board worked magic.
But normally, in the front.
Neither is really correct. A true twin places the fins closer to the tail that the front boxes on a tri or quad, but so far back as the trailers on a quad. But if you like the keels in either the front or rears of a quad, who cares.
