Jim,

You are on the right track.  I dream of a paper machine that could make a grade change in 5 minutes or less-not by smearing specs so that the grades over-lap, but by fast response of the machine's systems.

What would that mean?  Most significantly it would mean reduction of wet end volume from 1000's of gallons to an almost 'straight-through' system which would mean outstanding mixing and on-line process monitoring and control.  This concept is totally in-line with other LGMI concepts of a small, light, nimble, high-efficiency paper production system.

Getting rid of the headbox should be an integral part of that.  One should start by defining the purpose of the headbox such as "To properly (?) align fibers and distribute them evenly across the wire"  Experts could embellish this.

Like you, if a group of NASA engineers (and several are available) were engaged to design a system to accomplish this, I seriously doubt that we would recognize it as a 'headbox'.  Further, suppose they were able to design a system that could do that at 3-5% consistency rather than 0.1%; what would that do to the design of the machine.  That would be totally consistent with my goal of a short dwell-time wet end and fast grade changes.

The sad part is that our industry experts typically refine the design rather than replace the concept; we have very few 'paradigm-busters' among us.

Ed Turner