I believe the purpose of the glue is to fill in the area were you have used an abrasive to tear the surface of the tube. That is why you place a patch after the glue is dry. I have observed by the time it takes me to peal off a patch after applying a thin coat of glue on the tube, The glue has already set in. Blow on it if its still kind of damp. Also try rubbing out air pockets that can be trapped easily in the ridges of the tube. After Living in the south west, with thorn and all, paching tubes all sumer long is a way of life.