That model designed and printed for fan only and not for realy life use...
1. Do not scale the model (because of build in tolarences).
2. Print with 0.2 or less layer height.
3. Print with support (touching buildplace) only.
4. After print finished, remove the 2 structured supports (blue ones) like on the image i provided above.
5. With some force rotate the lock mechanism to break little structure dots inside (see the image above)
6. Enjoy !