I found a place that specialises in producing hemispheres up to SEVEN meters across!! I think they should be able to handle my puny requirements… Now with a little luck they’ll have an appropriate sized tool already which will save me a fortune, we might end up with a sphere larger than 1.4 meters but that’s better than paying the £15,000 one company quoted me for press tooling (!). Even if they can’t produce them to my exact requirements I’m sure someone else can cut off the edges and punch and tap the holes.

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