Strange effect with 4.5

[jaygeem 0]

I downloaded Cura 4.5 on my Mac, but all my prints now have a pattern on the surface (see the benchy). They printed perfectly with a smooth surface in 4.4.1. I was using 4.4.1 as it came without any changes, and the same with 4.5. What do I need to change to get my prints back to what they were with 4.4.1?

[gr5 2,172]

That looks like infill showing through.  You have a few options.  One is to make the walls thicker - it looks like you only have one pass on the wall so maybe make 2 or 3 passes.  Or maybe you already have 2 passes.  So set:

1) Wall thickness 2 or 3X line width

But probably the easier thing to do is just this:

2) check the box on "outer before inner walls"

 

Note that cura claims this can reduce quality on overhangs.  For some reason I don't get these lines without having to do #2 above.  Or maybe I get them but they are too difficult for me to see.  Note that shiny black filament shows imprefections more than any other type of filament but only if you hold it just right so the light reflects just so.  As you did here.  If you were to (for example) paint this with a flat matte color you wouldn't be able to see these lines.

[jaygeem 0]

Thanks, I will try #2 and see what happens. The lines are quite pronounced, so painting would not hide them. I would guess that they are around 1mm high.