How to cut a circular hole in a knurled surface

[nicolabirtch]

Hi,

I am try to model this knob with vertical ridges.
I can not figure out how to cut a circle out of it without deforming the ridges.
The only way I have found is boolean.
I tried displacement maps.
Using material displacement map almost worked, but left gaps on the top and bottom between the ridges.
Using displacement modifier with UV maps distorted the ridges around the hole.
Same with modeling.
Is there a way to model this without boolean?

Thanks

[SoundDifferent]

You can make a cylinder cut with boolean:

Then cut additional edges and remove extra vertices:

Then extrude cylindrical cut a few times to make a cylinder inner area, and because topology of initial cut are uneven, its better to make a few extrudes and gradually smooth them by smooth tool/manually, whatewer. You can use shrinkwrap to enitial boolean cutter here to make sure the cylinder are nice and round.

2 level of subd

[nicolabirtch]

Thank you,

that worked!