Self-building a fountain pen is basically possible; nib and feed are usually bought from the firm Bock, since the manufacture of these components requires considerable experience and special tools. Barrel, cap, mechanism and closures can be made on a lathe from suitable materials such as precious resin, acrylic, hardwood or metal. Anyone wanting to develop an independent filling system finds a practical reference, e.g. in the Bulk Filler system (Conid/Fountainbel), whose developer realised his own patented principle after several years of self-building. Due to the high artisanal and technical effort, self-builds are rare; collectors advise long learning periods and orientation toward established Bock nibs in order to ensure writing quality and ink flow.