Metal gears front differential

This is a project that combines 3D parts with metal parts made on a lathe and bought metal parts.

I kept breaking my internal gears in the differential and my u-joints, so finally I decided to use metal internal gears and metal u-joints. These two are bought.

These won't break the bank:

http://www.rchobbyestore.co.uk/rc-spares-c1/spare-car-parts-c2/gears-pinions-c49/hsp-02066-diff-pinions-pin-1-10th-scale-rc-parts-p605

For the u-joints I got these, 5mm to 5mm shaft diameter:

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