the mold was made inside the boat lined with big garbage bags, successive layers of foam would build up the area around the hips and under thighs as well as squishing up the end of the garbage bag gathered at my groin, Yikes!!

one one mold I had to use a chefs knife to cut myself out,,,but I digress. So the foam hardens precisely to the shape of you and what your wearing, when it hardens the foam that has risen up between thighs is solid, no fore/aft movement possible, move 1/2" forfward and its like sitting on a bicycle seat, so the plastic is all removed and the mold can be sanded/surformed down to allow for adequate movement. The hip braces are integral with the seat since the mold continues up the side to the coaming and your glass can continue up to the coaming, wax paper or plastic helped press the layup against the mold and covered coaming where my hips were no longer pressing against it. The mold had to be cut into thirds to get it out. Whole operation filled up a small garbage can with waste. added one of those 3/16" butterfly shaped seat pads to the seat,drilled holes to drain water, made hole for pump to fit into between thighs if needed. With minicell glued to inside of boat where seat rests about 1/2" off bottom of kayak, thick chunks 4"x4" of minicell connect sides of seat by 5200 to insides of kayak otherwise seat would flex excessively side to side.