Chamfered hole on outside of tube

[CraigerBrau]

I'm fairly new to CadQuery and cannot quite figure this out. I'm trying to recreate a part I designed in FreeCAD. However, I cannot isolate just the outside of the tube to do the chamfer. The chamfer is applied to both the outside and inside. What am I missing?

Thanks!
Craig

import cadquery as cq

(id, id2, h, t, f) = (45.04, 36.5, 33, 2.83, 0.25)

pt1 = 9.4/2
pt2 = 10.34/2
hole_h = 9.0
hole_offset = 10.95

holes = (
    cq.Workplane('YZ', origin = (0,0,hole_offset))
    .moveTo(pt1, 0)
    .lineTo(-pt1, 0)
    .lineTo(-pt2, hole_h)
    .threePointArc((1.0, hole_h+2.19),(pt2, hole_h))
    .close()
    .extrude(id/2 + t + 1, both=True)
)

body = (
    cq.Workplane('XY')
    .circle(id/2 + t)
    .circle(id/2)
    .extrude(h)
    .cut(holes)
    .faces("not %Plane")
    .edges("not <Z")
    .edges("not >Z")
    .edges("not |Y")
    .edges("not |X")
    .chamfer(1)
    .workplane(offset = -h/2)
    .circle(id/2)
    .circle(id2/2)
    .extrude(t)
    .combine()
)

show_object(body)

[lorenzncode]

Try this selector to select the outer face based on Area:

    .faces("%CYLINDER")
    .faces(cq.selectors.AreaNthSelector(-1))

[CraigerBrau]

Thank you so much. This change was what I was looking for.

    .faces("%CYLINDER")
    .faces(cq.selectors.AreaNthSelector(-1))
    .edges("not <Z")
    .edges("not >Z")
    .chamfer(1)

[lorenzncode]

Great. You can also make your own selector with sort.

There is an example in the docs using Volume. https://cadquery.readthedocs.io/en/latest/selectors.html#additional-special-methods

This would be equivalent area selector using sort:

    .faces("%CYLINDER")
    .sort(lambda f: f.Area())[-1]
    .edges("not <Z")
    .edges("not >Z")
    .chamfer(1)