How To
  1. create your straight rail lines for either top or bottom.
  2. start from one of the edges and go upwards, you want half the y distance including the straight piece.
  3. from here add the same distance from your downward rails to the side.
    4. you should have something like this now, place a rail piece one down and right (shown red) and connect your straight line to here.
  4. add the other curve remove the scaffold rails and copy the curves to the rest of the hexagon
  5. blueprint your hexagon add in the grid sizes and offset and off you go with perfectly tiling bestagons

Make sure to use an uneven amount of straight rails, and an even amount for the Vertical length and the Offset.

Uneven Offset should work in theory but the calculations will be off.