This is how many years ago Fred Bass advised me to clean the inside of the bowl:
Let the pipe cool
After emptying the ash double up a non bristle pipe cleaner and use to wipe down the bowl. May take several pipe cleaners.
When pipe cleaners come out clean then wipe the bowl with a paper towels until the paper towel comes out clean.
If there is still some buildup in the bowl use a blunt pipe knife to gently scrape the bowl. Empty the bowl to eliminate any residue from the knife scrapping. Then wipe bowl again with paper towels.
This is all I do to clean the bowl interior.
Let the pipe cool
After emptying the ash double up a non bristle pipe cleaner and use to wipe down the bowl. May take several pipe cleaners.
When pipe cleaners come out clean then wipe the bowl with a paper towels until the paper towel comes out clean.
If there is still some buildup in the bowl use a blunt pipe knife to gently scrape the bowl. Empty the bowl to eliminate any residue from the knife scrapping. Then wipe bowl again with paper towels.
This is all I do to clean the bowl interior.
