Tang's Window Cat Flap

Hello Instructables,  This is my first go at the visual learning style I have.  While not being able to calculate the necessary space for this exact Instructable yet, I go forward with the inspiration of Tang's Window Cat Flap.  Like I typed, there is never a way in my mind to be sure about the worthy and with that forgive any missing steps or coverage of tools.  This is the cat and my first go at this.                                         

Step one is need of a window and tools to modify a Plexiglas insert replacing the screen.                                                                                                                 

1    Next is lining the Plexiglas cut to size with a gasket to prevent cool air draft, I chose duct tape stuck around edges.                                                                                                                   
2     After cutting the specified entry for your size cat, save the cutout to trim and fit as the swinging flap, I also chose duct tape to secure the swing.  Gaskets included fabricated with duct tape.
3      Finally fit your project in the appropriate window housing and set loose with rolling open the actual window in this case doubling as the door lock.  What a grand idea just waiting to dissolve. Enjoy, and get a professional cut on the glass each time. My blade skills cracked my glass. 

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