Balsa wood pipe filter - has triangular cross-section milled so as to preserve natural configuration of wood

摘要

The pipe filters are cut from a block of balsa wood which has good filtration and absorption properties. The filters are prismatic pref. with a triangular cross-section and are milling into shape without disrupting the natural orientation of the wood fibres. Several filters are formed in a parallel configuration on a strip of wood and are snapped off as required. Each filter is inserted into the mouthpiece of the pipe and is changed when it is too clogged with tar and nicotine.