Any glaze, clay etc. that is fused to the Advancer shelf surface can always be removed with care due to the extremely low shelf porosity of <1%. Removing glaze runs, halos and any debris is recommended whenever it appears. You may use sandpaper, a scraper or a GlazeEraser® Hand Tool. This will help avoid long term buildup that could ultimately cause your pots to stick (given enough residue). In more severe cases of buildup, an angle grinder with an abrasive disk can be used for removal. Additional information on this topic is covered in our “How to Clean an Advancer Kiln Shelf” video on Kilnshelf.com.