Renn's stingers

Tolman skiff builders are always trying new ways of making the scuppers one-way on their skiffs. The idea is to have them open and draining the aft cockpit area when needed but closed and leak-free when not.

Some builders use flapper valves and ping-pong ball scuppers with mixed success. Here is a photo of what I'm doing which is basically just what Renn describes in his book.

I have a 3" diameter piece of PVC tubing epoxied into place, one on each side of the boat. There is plenty of surface protruding for me to slide the stinger on. Renn suggests using backpack material. It's waterproof and found at most larger fabric stores. The second photo shows how they are made. You just use rubber cement to glue two sheets flat together with just enough open space in the middle to slip over the the PVC. Then you stitch up each side. When there is water in the boat, these will open up and when the boat is dry, they will shut by themselves. You can also pull them up with a small line. I made mine 18" long which is just long enough to pull the end of the stinger up past the splashwell. 

 If for some reason, you want to shut everything up with little fuss, for less than $3 each, you can get plumber plugs that will go into the 3" PVC and seal the scuppers. These can be put in from inside of the boat.