I am a beginner and using Sketchup to design a barn for myself.
Sometimes I use multiple components which together make up a larger surface, in the example below this is the case with the roof. When I do this I see black outlines for the different groups. I found out I can hide lines but when I do there is white between the surfaces.
What is the best practice to prevent this from happening and what is the best way for me to fix this in my model?
It’s caused by “Z - Fighting” I believe. “Z -Fighting” is when two separate faces are touching and SketchUp can"t decide which face is in the front. Even though you hide the lines that run across the roof line you get that white "ghosting from the faces that touch.
A quick fix would be to erase the touching faces. Bigger issue is perhaps better management of how your using groups and components. Can’t make specific recommendations without actually seeing your model.
Ah the z-fighting explains other issues I have in my model, thanks. Not sure if the roof is also z-fighting as I believe the new component starts where the other stops. I don’t think they overlap.
The bigger issue is indeed better management of components. As I rarely use sketchup I only watched some basic tutorials that gave me just enough information to use it for my purpose. But the further along I get in my model the more it is biting me in the ***
Ran a little test before my first post to double check my supposition. Here’s a screen shot hope it makes sense. If you can post the model I’m sure you’ll get some good tips on better ways to manage things.
Each “block” is a group. When their in position on the left two faces touch. On the right I rotated the one piece so I could better indicate the touching faces.
@doing3dthingies, this issue of “bleeding through” is due to the internal faces that are right behind the roof face you are looking at. Hiding the edge isn’t enough. That face behind the roof face also needs to be hidden or somehow removed (deleted if possible)
Thank you both! I have deleted the internal faces that were bleeding through the roof and this fixed the issue.
@tuna1957 the screenshot definitely helps. I am sure I will get tips should I post my model, but there are so many things wrong with it that it won’t do any good I think. It is all smoke and mirrors, it looks good on the outside and the measurements are ok so it is just what I need. But modifying things is big trouble 
My model is almost finished. I will take more tutorials next time I am designing something.
This is the first tutorial to LOOK AT
