Aerofoils for my first fully printable plane

My first attempts at making an aerofoil... Still not working I will probably hit mk 20 at this rate before I get something flyable

mk1 warped like crazy and wouldn't hold it's shape

Mk 2 I learned how to add internal structure, but shape had insanely high stall speeds, maybe a Clark Y type aerofoil will work better

Mk 3 NOPE

Mk 4 okay maybe?...