A simple modification to Crab's excellent Eiffel-style sphere
The original circular joining plates are replaced by starfish-shaped plates. This makes the completed sphere look more like a mesh of straight girders and less like a surface covered in circles.
Follow the instructions for Crab's original. Just swap these starfish plates for the original circular plates.
It's drawn to cut from 3mm MDF.
You need to cut:
24 5-way joiners
40 6-way joiners
60 short 2-circle girders
30 long 3-circle girders
(spares as needed)
Glue is optional, but use superglue after assembly if you need to. Assembly is basically routine and simple, but does need a light touch â€“ the parts will break easily if squeezed at the sides. It takes me about an hour to assemble one.
I start at the bottom and work round evenly in circles. I fit the inside plate at each junction, then the girders, then the outside plate, then squeeze all the joints carefully home. Check before squeezing tight! It's probably impossible to dismantle one without damage.
Remember these rules:
- All sides of the 5-way joiners need 2-hole girders
- All triangles are made of two 2-hole girders and one 3-hole girder.
- All 6-way joiners have three 2-hole girders and three 3-hole girders.
I finish off by making a 'cap' of six triangles as a separate piece, then adding that to the almost-completed sphere. It gives more working space than trying to fit one last plate.
Files are produced for CorelDRAW X5. My machine is an Epilog 36EXT 75W, but isn't in perfect tune as yet and so takes about an hour and a half to cut a complete sphere.
Thanks Crab, I love your original!