The distance from skirt to pot, the gap, should be 10mm, otherwise it might choke your fire smile
Pot Skirt Investigation, ETHOS 2010

Code:
       |                   |S|
       |SCREW>>>>>>>NUT>NUT|K|NUT>>>>>
    P  |                   |I|
    O  |                   |R|
    T  |                   |T|
       |     -10mm-        | |
_______/                   | ||
\/\/\/\|                   | ||
/\/\/\/|                      |
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