The problem I came across were that if I resized a tyre, then the previously made tyre stack would also be resized to the incorrect dimensions…
(None of this has any connection to SketchUp layers which control visibility.)
The way I got round it were to make a tyre layer at a time, make the complete thing (tyres and sand) into a component being sure to set the component axis in the centre and then delete it. YES delete it. Even though it is deleted from the model space it still remains in the “In model components”, unless it is purged from the file.
I then made the remaining tyre layers, now able to resize them without affecting the sizes of the ones I had deleted from the model space, great stuff.
When I finished the last one, I made it a component (setting the axis) and deleted that. Then staring with the largest I brought them back in to the model space, stacking them up. Here`s the last part…
s probably much easier than I make it sound, although I have tried to explain as clearly as I can. Again, its probably not the “be all and end all” it`s how I found a way around the problems I came across.
Hope it helps.