Can anyone help me with my thatchy result?

[pancreasboy 0]

Hey there guys, complete noob to 3d printing here so please forgive my shameful questions. :)
 

Just trying to print these hinge pieces with PLA at 2.5cm long each, but walls arent that strong and the top and bottom are really thatchy. I'm printing them flat on the bed but should I be printing them at 45 degrees. My wall thickness in Cura is 1.2mm with a 3 wall line count with Infill at 80%. File was from here https://gumroad.com/l/HFUjr (which you can see they're really nice and thick, strong walls).
 

Thanks in advance.