Negative/Subtractive 3D Bodies?

[Pack34]

Is there a way to make a cylinder or similar Subtractive instead of Additive? Meaning to use a cylinder to punch a drill hole on a model.

I'm trying to make all my components as true as possible using the built-in 3D modeling abilities in AD17/AD18.

[julianhigginson]

I haven't checked ad18, but component bodies using extrusions are very simple in ad, and additive only... for anything complex, use proper 3d modelling software (even freecad) and export a stepfile you can then pick up in altium footprint editor.

[pigrew]

Nothing new in Altium 18, it still can only sum extruded shapes and spheres.

Personally, I find OpenSCAD as a very light-weight and quick way to make parametric 3D shapes. It's much quicker for me than FreeCAD. I use FreeCAD when I need to modify existing models.

[julianhigginson]

Oooh. Openscad? Thanks for the tip, haven't tried that before. Yeah freecad is a little clunky, but once you learn it, it's pretty useful.

[pigrew]

Oooh. Openscad? Thanks for the tip, haven't tried that before. Yeah freecad is a little clunky, but once you learn it, it's pretty useful.

OpenSCAD is a scripting language for parametric 3D modeling. The downside is that it's text-based so that may scare away many folks, but it's the software that I've felt the most comfortable with. The graphical editors like FreeCad just seem clunky in comparison when I want to input specific dimensions. One can't generate mechanical drawings or tolerance information from it, but it's great for day-to-day modeling for PCB software or 3D printers.

[T3sl4co1l]

Nope.

The workaround I use is arc segments.
1. With line and arc segments, draw the profile of the shape you want to make.
2. For circles, rubber-stamp them in the same location, and set the angles of the circles to 0-90 and 180-270 degrees.  This gives you snap points in the cardinal directions (make sure snap-to-object is on).
3. Place a 3DComponentBody.  Adjust the vertices to the snap points.  Grab the control point of a line segment, and press SHIFT+SPACE to cycle through the line modes.  Select the arc mode.
4. Drag vertices and arcs until you have the outline, and make a concavity that encloses the hole.  Close the concavity by dragging its wall vertices on top of each other, leaving a 'bubble' in the middle.  You can use two arc segments to make a complete circle; you use the 0 and 180 (say) snap points to position the vertices, and the 90 and 270 snap points to position the arcs.
5. If this shape does not lay flat, say it's a vertical wall with holes in it: open the Properties dialog and press Convert to STEP.  Adjust the angle and position as needed.

Example: https://www.seventransistorlabs.com/Images/Output%20Interposer%201.jpg
The cylindrical structure on the right is hollow; the plates on the left have rounded bends, and open holes (note the shoulder washers are open in the middle).

It's a pain, but this is the best you can do, short of a 3D tool.

No way to make compound bends (spheroidal, toroidal or saddle shapes, say).

Tim