<p>I am Attempting to print this, from Blender
<a href="https://i.stack.imgur.com/kKdun.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/kKdun.jpg" alt="enter image description here"></a>
But Cura decides to fill in the middle part of the model. 
<a href="https://i.stack.imgur.com/1fj3T.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1fj3T.png" alt="enter image description here"></a>
I exported and imported the model from an STL file.</p>

<p>If anyone can answer this, that would be greatly appreciated.</p>

[{'answer_id': 13720, 'author': 'LukeDunkley', 'author_id': 21277, 'author_profile': 'https://3dprinting.stackexchange.com/users/21277', 'pm_score': 1, 'selected': False, 'text': '<p>I would recommend using an actual CAD/CAM program, such as Autodesk Fusion 360, instead of using a 3d model program. Not only will this be able to directly export you finished model to Cura, and the models are made in a way that works with a 3d printing slicer, there will be more help around 3D printing for it.</p>\n\n<p>Although it is slightly difficult to use to start with, as you become more proficient, it is a very powerful tool to have. . Fusion 360 is free for hobbyists or students. See this link for help activating: <a href="https://www.autodesk.com/campaigns/fusion-360-for-hobbyists" rel="nofollow noreferrer">https://www.autodesk.com/campaigns/fusion-360-for-hobbyists</a>.</p>\n\n<p>Another option would be SolidWorks, although you do have to pay for this option, but it is much simpler to work with in my opinion.</p>\n'}, {'answer_id': 15676, 'author': 'Wolfgang Ponce', 'author_id': 26922, 'author_profile': 'https://3dprinting.stackexchange.com/users/26922', 'pm_score': 2, 'selected': False, 'text': '<p>Try disabling the &quot;Union Overlapping Volumes&quot; option on Mesh Fixes section. Worked for me.</p>\n'}]
['https://3dprinting.stackexchange.com/questions/12046', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/20170/']