Probably simple trim issue ...

 From:  DannyT (DANTAS)
5269.8 In reply to 5269.6 
Great start Jesper!

The volume of this part is 8368.18cm³ (510.66in³) also I noticed that your part isn't a 'Solid' so I had to trim it in half, mirror then join to become a solid volume, one side was good :)

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~Danny~