Here is an example of poor cake maintenance. There was recently another thread going around about cake build up and maintenance. This is an example of poor cake maintenance. Cake should be roughly as thick as a dime inside your bowl. You can maintain it with reamers or just the right pocket knife, but you have to be careful not to remove too much. Some people think that you should never wipe out your bowl and that doing so will inhibit cake formation, but I for one do wipe my bowls out and still build cake. The reality is that cake builds while you smoke and as long as you aren't scouring out the inside of your bowl, it will build. The pipe in this photo is the flip side however, this is of a pipe that was probably never cleaned. As a restorer of pipes I often come across pipes with so much cake that they are almost smoked closed. I know they are your pipes and maybe some of your will be buried with your pipes, but for the future generation of pipe smokers and restorers for that matter please clean your pipes and maintain your cake or this could happen to you!