Charcoal trick for 18"

[Brad Olson]

The coalgrate for an 18" kettle fits just inside the 18" WSM's fire ring. When one's installed at a 90-degree turn from the WSM grate a pattern of small squares is created, which means the charcoal and/or wood has to burn down to smaller pieces before it falls through. More burn for your buck! And grate-doubling works for kettles, too.

(Note: I have an older WSM and older kettles, so if Weber changed the size of the current kettle grate and/or fire ring this trick may or may not still work.)

 

[Lew Newby]

And here's a reference for that and other charcoal grate mods. https://www.virtualweberbullet.com/charcoal-grate-modifications/