3D Model to Pepakura Issues

[RomanW]

Hey Guys,

So I have dabbled in some of my own 3D modelling for the Reach CQB helmet, and all has gone great, EXCEPT for when I import the .obj file into Pep Designer. It seems that the program feels it is a good idea to create its own edges and faces, and also revers the angles so that the print out has some defects in certain places.

Has anyone experienced this before, and know how to fix it? I've had to import the model as an .stl file (Polygon) and this doesn't happen, but then I get a butt load of polys to sort through when unfolding.

Any help would be greatly appreciated!

Roman

 

[Chernobyl]

If you show me the file I might be able to provide some feedback for you.

 

[Lazarus215]

You might try repairing the model using Netfabb. That has solved some of my issues, I'm just trash at unfolding the things.

 

[RomanW]

Thanks guys,

Which file are you wanting Chernobyl? I can send you the .OBJ? I don't have a licence for Pepakura, and therefore don't have a .PDO file for you..

Roman

 

[Chernobyl]

The OBJ file will work fine. ZIP it up and attach it to your post and I'll take a look.

 

[KingRahl]

What program are you using? I know for Blender at least, when you export as .obj it combines everything in the scene into one object.

 

[RomanW]

Okey Doke, I'll do my best to attach it haha. Let me know if it doesn't work.

Yes, I am using Blender.

 

[Chernobyl]

Okey Doke, I'll do my best to attach it haha. Let me know if it doesn't work.

Yes, I am using Blender.

You've attached the wrong file - I'd need either the regular .blend file or a raw .obj file. I can't use a .blend1 file.

 

[RomanW]

Try this one.


[EDIT]
Any advice in regards to the model would be greatly appreciated too. It's my first remodel, and there are a lot of things I'm not happy with, and could improve on!

 

[Chernobyl]

Try this one.


[EDIT]
Any advice in regards to the model would be greatly appreciated too. It's my first remodel, and there are a lot of things I'm not happy with, and could improve on!

Right, that works a treat. My main concern is that you have some faces with too many vertices - try to link everything up so that your faces have a maximum of four (4) vertices. This is the major issue that's throwing your work off. I'm currently working on resolving the issues for you, and I'll post a file for you once it's complete.

EDIT: if this is a game model clean-up I could probably offer some tips to get you started.

Double Edit: she's done. Enjoy.

 

[RomanW]

Right, that works a treat. My main concern is that you have some faces with too many vertices - try to link everything up so that your faces have a maximum of four (4) vertices. This is the major issue that's throwing your work off. I'm currently working on resolving the issues for you, and I'll post a file for you once it's complete.

EDIT: if this is a game model clean-up I could probably offer some tips to get you started.

That would be great (To both things)! Thanks a bunch.

 

[KingRahl]

You've attached the wrong file - I'd need either the regular .blend file or a raw .obj file. I can't use a .blend1 file.

You just need to rename the file by deleting the number one. Blender renames the file this when you save again under the same name. This is good to use when you made too many changes to undo and you already saved.
RomanW
I think I found what the problem may be. When you export as a .stl file, every face gets converted into triangles. When you export as an .obj file all the geometry, vertices, and faces stay where they are. The thing to remember about .obj files and Pepakura is that you can not have any faces with more than four vertices. Now, you can try to convert all the faces that are shaped like "L" and turn them into two separate faces. OR you can use a shortcut and convert everything into tris then quads.

1. While in "Edit" mode select EVERYTHING.
2. Mesh - Faces - Triangulate Faces
3. Mesh - Faces - Tris to Quads

This will give you some triangles, but you won't have as many faces as if you made it an .stl.

A note on your face shield... The supports you have on the top crossing each other. If you look carefully, there's a twist in the faces. You'll have to remember that paper doesn't twist as easily as a 3D file. You may be better off just changing them to go straight across.

The support inside connecting both cheeks is going to be a problem. You'll need to remember that one edge can not connect more than two faces. That support will need to be moved down to the brim if you want it to work.

I hope this has answered any problems you had. Keep up the good work.

Edit: Wow. It took thirty minutes to type this? Chernobyl had already replied 26 minutes ago.

 

[RomanW]

You just need to rename the file by deleting the number one. Blender renames the file this when you save again under the same name. This is good to use when you made too many changes to undo and you already saved.
RomanW
I think I found what the problem may be. When you export as a .stl file, every face gets converted into triangles. When you export as an .obj file all the geometry, vertices, and faces stay where they are. The thing to remember about .obj files and Pepakura is that you can not have any faces with more than four vertices. Now, you can try to convert all the faces that are shaped like "L" and turn them into two separate faces. OR you can use a shortcut and convert everything into tris then quads.

1. While in "Edit" mode select EVERYTHING.
2. Mesh - Faces - Triangulate Faces
3. Mesh - Faces - Tris to Quads

This will give you some triangles, but you won't have as many faces as if you made it an .stl.

A note on your face shield... The supports you have on the top crossing each other. If you look carefully, there's a twist in the faces. You'll have to remember that paper doesn't twist as easily as a 3D file. You may be better off just changing them to go straight across.

The support inside connecting both cheeks is going to be a problem. You'll need to remember that one edge can not connect more than two faces. That support will need to be moved down to the brim if you want it to work.

I hope this has answered any problems you had. Keep up the good work.

Edit: Wow. It took thirty minutes to type this? Chernobyl had already replied 26 minutes ago.

Haha thanks King. Yeah Chernobyl is a beast at this forum stuff. I noticed the visor supports after the face once I had printed out the patterns and test build that piece. It stays pretty solid with only one brace, so I may stay with 2 upper braces (One on the top, and the upper rear), but being the perfectionist I am, will probably change them to support as much as possible. (I wish I had a 3D printer.. this wouldn't be an issue lol). As for the one inside the helmet, I knew it wasn't going to "work", but I was planning on cutting out tabs for it to secure onto anyways despit Pepakura Designer not adding them. If this file gets used on the archive (after much fixing) then maybe I would change that. GothX's file is great.. but I had some issues with it when I built it, and wanted to try my own hand (and ideas) at this stuff.

Well I now see why things were so messed up, if Pep can only handle 4 vertice faces. Good to know for future clean-ups!

I did have another question.. How do I make this thing symmetrical? Like I said, I've printed this out and have started building it, and some pieces have different dimensions, and aren't shaped exactly he same, and blah blah. Is that just the painstaking part of modelling, or is there an easier way to cut the model in half, and then mirror it? (Especially for those 'canisters' on the side. If you look at them, they are different in dimension)

Thanks!

Roman

 

[Chernobyl]

I did have another question.. How do I make this thing symmetrical? Like I said, I've printed this out and have started building it, and some pieces have different dimensions, and aren't shaped exactly he same, and blah blah. Is that just the painstaking part of modelling, or is there an easier way to cut the model in half, and then mirror it? (Especially for those 'canisters' on the side. If you look at them, they are different in dimension)

Thanks!

Roman

You can add a mirror modifier via Properties > Add Modifier > Mirror. That said, I simply cut your work in half along the Z axis, worked on one half, then duplicated, mirrored, removed doubles, and normalised everything before saving.

Edit: Wow. It took thirty minutes to type this? Chernobyl had already replied 26 minutes ago.

Gotta go fast!

 

[KingRahl]

When using the Mirror Modifier, remember to check mark the "clipping" selection. Using the mirror modifier will put a Edge Loop down the center.

I hope this video helps.

 

[RomanW]

Awesome thanks you two!

Chernobyl, when you say "normalised everything", what do you mean by that?

 

[KingRahl]

Normals are the direction the faces are facing. You'll want them all facing out, but at least in the same direction. It's explained a little in this video.