I bought my CGSP w/SFB last Christmas & have used it at least 2 or 3 times a month (just about every other weekend). Most of the time I have a drip pan in the bottom with either some water or beer. I line the bottom with alum foil & change it about every other smoke. I smoke meat at temp 225-250. I noticed after the last smoke (2 8lb briskets & a rack of pork ribs) that I might consider cleaning the lid. The lid was coated with "black gum---almost tar like). I hung the coal tray in the main chamber, put 1 chimmney of lighted coals & closed the lid & opened the lid for the FB. I didn't have the grates in it, thank goodness. When I checked later..........there was black tar drops coming out of the exhaust & globes of the black gum that had fallen off the lid. I loaded another chimney & the gum became ash etc. I removed the lid & scraped it down real good. My question, is this normal build up ?