The below blocks are missing their recipes:
Aluminum Machine Hull
Iron Machine Hull
Bronze Machine Hull (spelled Brone in game)
Brass Machine Hull
Steel Machine Hull
Titanium Machine Hull

Versions used:
TechReborn 0.3.0.729
IC2 Exp 2.2.759
CodeChickenCore 1.0.7.46
NEI 1.0.5.111

We haven't got machine parts item to craft the hulls. Should it be added?

If you do add it, the recipe it uses, as follows:

Is currently being used as a placeholder recipe for 360K helium coolant cells.

I will add it, and change the helium cell recipe.