How to make a hex grid?

I need to make a hex grid in Illustrator. There are two catches:

1) The hex grid is a particular shape: I'm looking for an easy way to put together a particular pattern of hexes.

2) There can be no duplicate lines. So I can't simply cut & paste the same single hex over and over, because everywhere the hexes overlapped there would be two lines. The final graphic from this is going to be output to a laser table. Anywhere the data shows two overlapping lines, the laser will burn twice, which ruins things, and could even be a fire hazard.

So pardon my newbishness, but would any of you care to offer pointers?

Thanks in advance.