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Countersink hole from opposite face

tom_augertom_auger Member Posts: 115 ✭✭


The above is an extruded shape. I'm using the Hole feature and the points for the holes have been drawn on a plane derived from the "bottom" of the shape. Thus, the countersink is at that location. I'd like the countersink to start at the opposite face, to create a countersunk "pocket" hole in the curved face. The hole is not normal to the curved face.

A manual strategy would be to offset the drawing plane for the hole by eyeballing it to match where I think the hole would intersect the curved face, but if I ever changed the slope of the curve, or adjusted some other aspects of the drawing, the hole would no longer align.

I'm wondering if there is a parametric technique I'm missing? It would be cool if you could chose which "end" of the hole the countersink starts from...

edit: tag: "farside countersink" - obviously I'm not the first person to wonder about this!

Best Answer

  • owen_sparksowen_sparks Member, Developers Posts: 2,660 PRO
    edited September 2019 Answer ✓
    Howdy.
    Good news; that's an easy fix.
    A hole will be projected either up or down from your sketch point. As your point is in the middle you only have "half a hole". 
    One thing that is not obvious at first is a counter-bored hole will be projected towards a part and respect the minimum CB required.  There is no need for the sketch point to touch the part, it can be above it if that makes positioning the sketch easier.
    Example:-

    Ensure the "Start from sketch plane" option is unchecked:-


    Hope that helps,
    Owen S.
    Business Systems and Configuration Controller
    HWM-Water Ltd

Answers

  • tom_augertom_auger Member Posts: 115 ✭✭


    This is unfortunate. Sorry, it's not obvious from the viewing angle, but the hole is clipped at the intersection of the plane and the surface being "drilled".

    Here's another view.


  • tom_augertom_auger Member Posts: 115 ✭✭


    okay at this point I'm just going to assume the tool just doesn't work properly on curved surfaces and will focus on extruded shapes and a boolean subtract.

    I'd love to get some seasoned veterans' opinions on this particular design challenge.
  • owen_sparksowen_sparks Member, Developers Posts: 2,660 PRO
    edited September 2019 Answer ✓
    Howdy.
    Good news; that's an easy fix.
    A hole will be projected either up or down from your sketch point. As your point is in the middle you only have "half a hole". 
    One thing that is not obvious at first is a counter-bored hole will be projected towards a part and respect the minimum CB required.  There is no need for the sketch point to touch the part, it can be above it if that makes positioning the sketch easier.
    Example:-

    Ensure the "Start from sketch plane" option is unchecked:-


    Hope that helps,
    Owen S.
    Business Systems and Configuration Controller
    HWM-Water Ltd
  • tom_augertom_auger Member Posts: 115 ✭✭
    Tried it as you suggested, Owen. Worked exactly as advertised. Where I had messed up was the position of my drawing plane - I was thinking in terms of where the center point of the hole would pierce the face, as opposed to the outer edge of the counterbore, which would require my plane to be considerably higher up.

    Thank you for the excellent advice!
  • owen_sparksowen_sparks Member, Developers Posts: 2,660 PRO
    Sure thing, it's like that here. 
    Glad you've got it working :+1:
    Owen S.
    Business Systems and Configuration Controller
    HWM-Water Ltd
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