Geodesic Dome 3V Connector for 1" PVC pipe

Geodesic Dome Connector for schedule 40 1" PVC pipes 3V

for detailed calculation of pipe length etc, refer to

http://www.acidome.ru/lab/calc/#7/12_Piped_D70_3V_R2_beams_30x30

you could scale this models to fit any size pipe theoretically.
5 pointed hub is for center of pentagon, 6 pointed hub for center of hexagon,
and 6 pointed hub with "P" is for the remaining, P should point to the pentagon.

protruding rods have diameter of 26.4 mm, which should fit tightly in schedule 40 pipe.