Now, aim the flame toward the shoulder of the seal, so that only the splash of the flame (if at all) touches the small tube. Like the straight seal, you are heating only as long as it takes to melt the folds. If you heat more of the small tube than desired, you end up getting too much glass involved. This will make the seal more difficult to complete and the seal will not look as good once finished. Like all operations, maintain a slow steady rotation of the glass.
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