This is an inconsistent but frequent issue. Often a solid surface will hide guide lines or make it impossible to accurately place lines and shapes on the surface because the preview guides are all hidden behind the surface. I checked to see if for some reason the surfaces don’t line up on the axis, but they seem to be coplanar. The workaround is to erase the surface to make it 'transparent, but quickly Sketchup will create a new surface. So it’s quite annoying and time consuming.
I have been using Sketchup for many years, but this is a new issue that has been plaguing me for the last couple of years. I also checked this on different versions and it seems to be the same issue on the older version 15.3 I still have, the current version and Sketchup Pro I used to have last year. I run the latests macOS10.13.2 on a 2.6ghz i5 with 8 gigs of ram.
Do other Mac users have this issue? Is there a preference that I selected mistakenly? Thank you for your time
Well it’s hard to figure out exactly what’s happening for you without more info. Can you post an example here? You can upload a model directly or even post some screen shots.
What are you calling a preview guide? Sketchup will not make faces spontaneously so you must be doing something to recreate a face. Have you used x-ray to see through geometry.
A bit more information would help to pinpoint the problem.
I have no particular trouble seeing guide lines that are positioned on faces. I use a Mac with SketchUp Pro 2016, 17, 18 currently. Here is a sample drawing, with a 5-inch radius disc that has two guide lines pulled up from the red and green axes:
What is the dimensional scale of the faces and edges nearby a guide line that causes trouble? I’m wondering if you are zoomed out very far or very close, which is causing some graphics issue? In my case, I typically work on objects that are from say 0.1 inch to 100 feet in extent, all located close to the world coordinate-system origin.
