You would have better luck resizing the graphic image you are trying to mate up
with.
The solution that I have used in the past (one that I "borrowed" from another
designer) is to use a rectangular grid instead of trying to exactly match up
the hexes. If you create a rectangle grid that has the corners of the
rectangle touch the center of the NW-NE-SE-SW edges of a points up hexagon,
then your grid will repeat regularly 2 rectangles wide (the central rectangle
that defines the cell and half of the rectangles to the immediate left and
right) and 1 rectangle high per hex. Rectangular grids work better than hex
grids because you have freedom to modify both height and width independently
from each other. It may take a bit of experimentation to dial in the proper
dimensions for your rectangle, but it can be done. The key is to get your
rectangle width to be exactly half of your hex width and then adjust the height
to match the hex edges.
The same concept can be modified to work for a flats up hex as well by rotating
everything 90 degrees.
Sigh. It's really much easier to do than it is to explain. I could email you
a gamebox created with the concept if you are interested.
