One end of the base tube of the T seal should be closed off with masking tape and a narro, hot flame should be directed at the location where you want the T seal attached. The trick here is to not linger any longer than need be. The longer you apply heat to the base tube, the more likely it will loose its rigid form and cease to be a straight base tube. Blow the side out just like the end of a capillary tube. If you control your breathing properly, you will create a thin top and thicker sides. When this is poped open, it will make a nice crown of glass to seal onto.
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