Remember that after weapons we need to make:
-models + animations for missing critters
-special death animations and missing one for PC's
-models/textures for armors/helmets
-Particle effects (Explosions/flying rockets/plasma or something like that - provided that devs want to change it)
Even if we manage to finish weapons in 2-3 weeks(It is possible with so many helping people
) - we need to wait for basic armor/player/player head model to start making clothes + critters based on it.
Making animations is only for specialists in this field. I don't know if we have any suitable people. Learning this stuff takes some time so I bet that 3d PC's will see the sunlight in aprox 4-6months
And it's very optimistic view!