Greetings,
I am trying to model a Boeing 767-300 series. Ready to paint the rear section of the fuselage, and used the knife tool to start the coloring process.
Saw distortions in the fuselage afterwards, and am completely stumped about how to correct.
See photo…
Regular email is [email protected]
Any help is greatly appreciated….
In Object Mode, press W and choose Shade Auto Smooth. This should remove the artifacts. If not, you’re going to have to retopologize
I can’t really see what you’re doing there; the image is too small since it’s in portrait mode rather than landscape – might want to figure out how to take screenshots straight from Blender (sorry, I can’t help with Macs).
It vaguely looks like you could have some extraneous geometry along the diagonal cut; select your entire mesh in Edit mode and do a Mesh → Merge → By Distance and adjust the distance to see whether that helps.
And as Joseph said, Shade Smooth. Also, your topology could be better. You have those loooong rectangular polygons – you generally want squarish quads whenever possible both for shading and for painting reasons. Add some loopcuts to even that out.
Maybe I misunderstand but:
I take it you are “cutting into pieces” the fuselag to apply different materials to different faces.
This is not generally a good idea, and can lead to you messing up the model’s topology.
It would be a more standard workflow to UV Unwrap the entire fuselag and give it an image texture and paint the colours in the image.
Didn’t want to actually separate parts. Tried that already and learned the hard way EXACTLY what you said. All I wanted to do is create a border with crisp, sharp, clear lines for different colors.
You understood correctly.
That UV stuff gives me the creeps….trying to avoid that for now. Wish there was a way to spray paint the fuselage somehow.
Unfortunately even if you do not separate the parts and just use the knife tool to add edge loops, the new loops will effect your shading.
If you want to learn 3d modeling and texturing you will have to learn Uvmapping.
I can understand your fear of UV unwrapping, it can be a pain, but it is the standard for exporting your models with detailed textures.
Assigning solid colour materials to different faces is very a limited workflow.
You will not be able to export procedural textures, they have to be baked which again means UV Unwrapping.
There is a way to spray paint the colours using “texture paint” mode. Texture paint needs an image texture to use as a “canvas”. You have to map the image to your model somehow (UV stuff!).
I am sorry to tell you that sooner or later you simply can not avoid UV’s.
Mr. Norman,
Took your advice, and made my first attempt at UV unwrapping……along with using the masking tool.
Still getting, rough, pixelated edges between colors. Surely there is a way to either prevent it from happening or correcting it.
If I can get a sharp, crisp line between the two, then my goal is accomplished. New at this and still don’t understand why painting angled faces is so hard…
Any way to correct this?
Thanks
All non vector digital images (bitmaps) have this problem, they are made up of little squares. When you draw a slanted or curved line there will always be this jagged effect when you zoom in.
There are 2 ways to minimise this effect.
Resolution:
Give your image more resolution, the jagged edge will still be there but you have to zoom in a lot more to see it. The higher the resolution of the image you are painting the less noticable the jagged edges will be. When you create the new image to paint on, instead of the default 1k - 1024 resolution use 4k -1024 x 4 (4096) or 8k- 1024 x 8 (8192). 4k should probably be enough.
Brush falloff:
Do not use a “hard brush”, use a brush with a little falloff this will give you a smother transition between one colour and another. You can adjust the falloff in the brush falloff settings.
Most people use both these methods, they make their textures as high res as possible and use “soft brushes”.
Unfortunately the higher the texture resolution the slower it is to calculate, this is very important for game engines this is why many people supply models with different texture resolutions to choose from (4k, 8k etc).
Thanks again for the advice!
Another question for you….
Why does the green material go BEYOND the two knife tool loop cuts that I made in the cylinder? I want the green to be assigned to the faces that I selected…
Why does this happen, and how do I correct or prevent? I am in Blender 3.1.
Do you have a subdivision surface modifier?
Yes, I do. How will that help?
Turn it off, and you’ll see the lines where you expect them. Or, add loop cuts to control the boundaries better with Ctrl R
Hi to paint a line,
1 set the stroke to line
To, paint on bothe sides at once
2 trun off Normal Falloff
3 uncheck Occlude and Back face culling.
( I also set spacing to 1% in stroke settings)
Click and drag to paint the line.
Painting curves is a little more difficult, here is a video, ( he goes a bit fast ):
It is a little tricky to get used to how the curve is created, you will have to practice a bit!
Thanks man! So there is NO cutting at all???
Hallelujah!!!
No it is best to avoid cutting the model up for textures as it will mess up your mesh. 
Great! Thanks again.
