economic production value of the machine is lost while disassembled in addition to the labor value of disassembly and reconstruction this invention is conceived to minimize both 34 down time 34 and maintenance labor thereby improving the 34 accessibility 34 of the slice plenum operatively the papermaking stock is pumped to the supply manifold 10 for final formation processing through the conduits 11 by generation of microturbulence which tends to disperse agglomerated fiber bundles these dispersed turbulent flow streams are delivered to the slice plenum 13 for slice configured discharge from the nozzle opening 17 onto the traveling fourdrinier screen in a manner well known to those of ordinary skill in the art the very nature of the papermaking process requires an application of materials having great natural affinities for bonding to adjacent surfaces including conduits and containers resultantly many interior surface areas within the headbox including the slice plenum 13 accumulate surface deposits of furnish constituents although many such deposits are removable by hot acid or caustic boil out processes others such as unreacted alkylsenic succinic anhydride asa size material are extremely tenacious and require vigorous mechanical scouring for removal care however must be exercised in the selection of tools and materials to be used on the polished internal headbox surfaces.