Ben from the Water Tribe has kindly written up a piece on how he has fitted a sail onto his Fethercraft K1 , he’s made up the hole sail himself , but the same idear can be yoused for fiting flat earth sails , his blog is good to !
1M Kayak Sail
The base of the mast is in compression and on a standard composite kayak, the standard approach is to reinforce this area with extra fiberglass and/or carbon fiber. Obviously, on a folding kayak with a soft fabric skin, this is not an option. In order to provide a solid base on which to mount the sail, I built a custom fiberglass and carbon fiber “plate.”
|Carbon fiber mast base plate|
I chose to locate the plate at the second structural frame, so the mast load is shared by the plate, deckridge, and frame. Having chosen the location for the plate, I covered the boat with parchment paper (great mold release), laid the fiberglass and carbon over it, then just had to wait for everything to get hard. A day or so later, I trimmed the plate down to size and applied some varnish to protect the epoxy.
Next was a way to keep the plate in place. First, I added some adhesive backed 1/8″ minicell foam to the bottom of the plate where it contacts the gunwales and deckridge. This provides some grip, and protection for the skin. Next, I added four D-rings, one at each corner of the plate.
|Additional D-rings glued to the hull skin of the kayak.|
I used these rings and the cleats mounted on the plate to lash the plate to the deck. This held the plate very securely, and there was no possibility of it moving or sliding around.
Now that the mounting plate was complete, I needed to add the rigging. The side stays were terminated to the rear D-rings using some small shackles. This allowed me to easily remove the stays for traveling. I added one more D-ring for the mainsheet block, and also used it to connect a rear stay.
I don’t have any good detailed pictures of the whole setup, but this is the closest I have.
The mainsheet (red) d-ring is just in front of the compass and the forestay (green) is connected to the bow carrying handle. The mainsheet and forestay are cleated by the cockpit using simple plastic clam cleats, which can be seen in the lower left corner of the picture above. The cleats were connected to the boat using a small loop of line through the rear mounting hole of the cleat and then looped around the deck rigging. With tension on the lines, the cleats were held straight enough that the line would not pull out.
Overall, the mounting system has worked very well for me so far, and I am very happy with it. It is lightweight, and easy to remove from the kayak. The only permanent modifications to the kayak are the four d-rings for lashing the mast base, and the d-ring for the mainsheet / rear stay.