Since my last post, I affixed the tire stem cap to the timer's winding stem using some epoxy clay. This morning, I attached the timer and rigged the rubber bands. One band is attached to the side of the rocket with a piece of Gorilla tape. On the other side, another band is tied to a short string and that to the release pin. I attached the cable-tie jammer to the launcher with some kite string. Here is a short video of a short time setting. I'll need to play with the timer to get the right time delay. Photos can be found in my Manatee Water Rocket album. I hope to fly her tomorrow.
P.S. Add some bailing wire and this rocket would fit in a redneck joke.