‘Breaking in a pipe’ means the accumulation of a protective carbon crust, which consists of ash particles, rests of tobacco and burned natural sugars. The so called cake will coat the inside of the bowl evenly, and protects the wood from the heat and absorbs condensates and moisture.
And how does it work?
We could confuse you with a multitude of theories and cause a great uncertainty and rob you of all the fun that means smoking a pipe.
Here is our favourite: Completely fill the pipe and then fire at will!
A few decades ago, millions of people just smoked a pipe withoutt thinking too much into it. Why complicate things now?
Break in paste?
Here we do not want to be dogmatic either… not even the pipemakers, who know most about this subject, have the same opinion. Some deliberately do not use paste, to preserve the beauty of the wood in the inside of the bowl. Others are afraid of burned pipes, and coat the pipes with the protective paste.
The break in paste that really helps building up a carbon crust, usually consists of sodium silicate, also called water glass, and fireclay. The rougher the paste is applied, the faster the crust will build. Ideally the paste is applied in multiply thin layers, and each layer has time to dry out.
Series pipes sometimes look as if they are protected, but the coating is just black stain. In summary, you have to ignore a lot of rules to burn a pipe through to an irreparable state.