I want to make some oil and vinegar bottles, and don't know how to size the stoppers. Do I need to order ones that are tapered? I remember Bill Van Gilder saying if the top of a cork fits the freshly thrown bottle opening, the bottom of the cork will fit the glazed and finished opening after shrinkage due to the taper. I am wanting the rubber stopper with the metal pour spout sticking up out of the stopper, and a flap to cover the opening of the spout.
I have looked at a bunch of pour spouts on line and I can't tell if they are tapered or not. Any advice?