Chamfered edge

Rhino
1

I am looking to add a 3mm chamfered edge to this part, but whenever I do it it creates a separate body. How do I create a chamfered edge around the edge of the pickguard

Screenshot 2023-08-09 at 5.53.36 PM
Screenshot 2023-08-09 at 5.53.36 PM2096×960 343 KB

2

Troubleshooting is easier if you post your Rhino file.

3

Hi Delayna -

From your other post, that object is 2.5 mm thick?
Also, curves that are created in a 2D illustration app often have continuity issues that make them poorly suited to be used to create clean 3D geometry. Just from the picture, that might look to be the case here, as well.

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image907×299 39.6 KB

But, as Martin wrote, without a 3dm file, all we can do is guess…
-wim

4

Pickguard.3dm (2.5 MB)

5

Thanks.
The object in that file is 0.1 mm thick. I’m not sure how you’d put a 3 mm chamfer on an edge here?
-wim

6

pickguard mm.3dm (2.8 MB)
Here it is in mm…not sure if I should just start from scratch to add a chamfer or if I should use the ai file.

7

Hi Delayna -

Thanks.
In this file, the thickness of the object is 2.6 mm. This is still less than the required 3 mm?

You should start from scratch. Many of the side surfaces aren’t even tangent to each other. I would expect curvature continuity here… And the holes aren’t circular.
-wim

8

I am able to get a chamfered edge the thickness of my material (2.6mm) But it creates 2 separate bodies. Is this caused from using an ai file or is there a step im missing

Screenshot 2023-08-11 at 1.48.45 PM
Screenshot 2023-08-11 at 1.48.45 PM1838×894 65.6 KB

9

Hi Delayna,

In this case it is a symptom of a less than ideal curve. I would recommend building a new nurbs curve in Rhino, extruding that to create a new solid, more than 2.6mm tall, creating the chamfer and then cutting away the extra height below the chamfer. It should be possible to get to a pickplate like that:

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image1087×707 148 KB

  1. Take your original curve and copy it to a new layer (that way you can modify the new version while keeping the original as a visual reference).
  2. Split the copy at the inflection points (where the curve changes from positive to negative).
  3. Use _Rebuild on each curve (apart from the straight sections) to make its degree three and its point count as low as possible while still being able to match the original. You should be able to get down to between 4 for gentle curves and 7 for the sharp ones. Select each rebuilt curve and tweak the positions of its control points to bring it closer to the original.
  4. Use _Match with the average curves option to make sure your individual sections join tangentially.
  5. You may need to iterate through the control point tweaking and the match steps a few times to get to a finished curve.
  6. At the indentation at top and bottom, delete the quarter circle arcs and recreate them using _ArcBlend to join the lines to each side.
  7. Join all the curves and extrude them into a solid 4.6mm high.
  8. Use _ChamferEdge to create the chamfer. This should go cleanly with this form and a clean curve but you might get artefacts at sharp angles and need to do some trimming.
  9. Use _WireCut to split the solid along the bottom of the chamfer and delete the unwanted part.

I have listed various commands you will want to use but I haven’t detailed the specifics of how to use them. The Rhino help file will give you that information.

HTH
Jeremy

10

An alternative to extruding the surface and then chamfering the edges is to create the edges directly using ExtrudeCrvTapered.

1 Like
11

@davidcockey’s suggestion is much more sensible. A helpful reminder that there is usually more than one way to do something in Rhino - we just need to raise our heads from time to time and see the wood instead of the trees.

Regards
Jeremy