  The usual wavemaker theory hides an unjustified integration constant
assumption that renders it invalid. We discuss some surprising subtleties of
momentum flux in infinite waves, packets and some counterintuitive examples
where "hidden" flux contributions can arise. From here, we construct an ideal
wavemaker that builds Airy waves from a series of microjets that allows an
exact calculation of the forces on boundaries. This allows us to also compute
the fluxes of all conserved quantities directly and rule out some of these
hidden contributions to momentum flux. We then discuss some realistic flapper
wavemakers and the trouble vorticity sources can create in the resulting fluid
motion. Along the way we present a completely local derivation of the group
velocity using fluxes.
