Alex Terrell wrote:
It's often suggested that a catapult on the moon could fire material
from the surface to L1. From there it would be sorted and grouped, and
then sent off in big cargo ships to colony construction sites at L4 or
L5.

How much delta V is required for this trip? And how long would it
take? My guess is it would be more of a time problem than a delta V
problem.

It's on the order of the escape velocity.
Say 2000m/s.
Maybe 5-10% lower, I have not done the numbers.