Fixing Series: Error No.3 - Reversed Normals


“But mostly I hate the way I don't hate you,
Not even close, not even a little bit, not even at all”

Ten Things I Hate About You

When first hearing the term ‘reversed’ or ‘inverted’ normals you’d be forgiven for having flashbacks to your early teenage years when you were unceremoniously divided by your peers into two distinct categories: normal and not-normal (also commonly known as a weird-o).

Weird "o"

It’s hard to imagine the ignominy that would have come with being labelled a ‘reversed normal’ during these formative years - some part of you is normal, you were so very close, but then you had to go and mess it all up. Typical.

As this fixing series progresses, it seems like each error we encounter exudes a similar stereotype, as if they could be defined by who they hung around with in High School. You remember the movies - there were the Jocks, the Cheerleaders, the Nerds (with many subcategories), Goths, Stoners, Hicks, Creepily Mature Students, Anarchists…the list goes on.

So far we’ve encountered the Bad Edges, who are to be avoided at all costs; the Holes, whose vacuous presence contributes as much to proceedings as the Stoners and now we have the Reversed Normals who elicit images of a student forced to face the corner of a room with a dunce cap on.

Fixie 3d printing inverted normals graphic

Obviously, we need to be a little more sensitive in our treatment of reversed normals these days. After all, they’re just faces looking in the wrong direction. Most softwares will give you the opportunity to highlight the direction of faces/normals. However, rather than making a show out of them, or out of yourself for your hasty modelling, they just need to be given a little nudge in the right direction. It’s imperative that all normals be facing the right direction so that the 3D printing software recognises the areas that are internal, between two external edges and thus communicating a solid printable volume (remind yourself of some of the guiding principles of 3D printing).

If Ten Things I Hate About You taught us anything (and it most certainly did), it would be that first impressions do us no favours. With a little bit of patience, encouragement and self-reflection, any file can be made printable.

So, even after the mess you arrived in and our initial opinion of you, we need to own up to the fact that this was a superficial appraisal. We do not in fact hate you. Now we see you. We see the 3D print you could be. We don’t even hate you a little bit, not even at all.

*Annnd cue: slow clap*