Hello!I created a model for 3D printing in 3DsMax 2019. When I use STL check modifier it says there are no errors. When I export file from .max to .stl suddenly open edges appear.How to avoid that? Am I using wrong settings for export?Model was created using Boolean and then converted to Poly. Can that be an issue?
.max screenshot
.stl screenshot

Please help me finish my college project)