Not to discourage your skeg building experiments but you may want to take a look inside your boat. I paddle a lot of whitewater in an 8 1/2 FT boat that spins easily and is not known for tracking. I have spent a bit of time making the boat fit very well (snug). The fitting includes foam contoured bulkhead for feet, backband, thigh braces, knee pads on the outside against the hull and most importantly hip pads with hooks on top. This may or may not be a bit much for a touring boat but it is very comfortable and the boat is not sloppy. By sloppy I liken it to trying to down hill ski with your boots unbuckled. It is really hard to make a boat go straight if it doesn't fit. After a really hard day of paddling it is usually my stomach mussels that are the sorest because they are what transfer your paddling strokes to the boat and I hate to do sit ups. The skeg will definitly fix the problem but you may find you can control the boat with a better fit and not give up manuveravlity when you want it. I have an old solom boat that used to feel hard to control (no outfitting) and I made up a temporary fin that I would duct tape on for flat water paddling. After a while you just don't need it anymore. Even if you do go with the skeg you would not regret working on a nice comfy fit on the inside. Steve