A Dozen Prisms
As a companion piece to the A Dozen Centered Squares here is a similar exercise in 3d.
Model a simple prism, 25 mm diameter, 10 mm height, 5 sides on top at a 10 degree angle. To keep things consistent, create 4 constants (with Equation) called diameter, height, facets, and angle and use those constants when building the part. If you try this, build it so that you could change any of the 4 constants and have the part rebuild properly.
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1. Extruded Segment with Patterned Body
Draw the profile of a segment. Extrude the segment to height. Draft the top face 10 degrees (use "Right" plane appropriately). Pattern the whole body. It creates a 5 piece multibody. Combine the multibodies into one.
2. Extruded Segment with Patterned Features
Follow the same construction as in the previous. Draw, extrude, draft, but then pattern the two features instead of the whole body. It will create a single body and save you a feature.
3. Extrude Block and Cut Segment
Instead of extruding down, extrude out the front. The extrusion has the face angle built in. Use second profile to cut the segment. Pattern to complete the part.
4. Layout Sketch
Create a layout sketch that contains the segment profile and construction geometry to create a plane for the facet face. Create a plane at the bottom then extrude up to face. Pattern to complete the part.
5. Layout Sketch with Offset
You can save yourself the bottom plane from the previous, but using Base>Extrude>Offset. You use the layout sketch, but tell the software to start the extrusion offset by 10 mm below the sketch plane. Direction1 becomes up to face. Again, pattern to complete the part.
6. Extrude Cut the Pattern
Instead of extruding the solid, cut extrude the facet. This is not a cone, so you cannot revolve the cut. Do a midplane extrusion to cut the first face. Then pattern the cut to complete. Note: if you cut all the way through the part, this won't work.
7. Use Cut with Surface
Use an axis (intersection of Top and Right) to create the plane for the top face. Sketch the segment oversize and create a planar face. Pattern the face and knit it. You can then use the combined surface to cut a base cylinder. Delete the surface body to only keep the solid.
8. Use Replace Face
This is basically the same as the previous, but instead of Cutting with the Surface you just replace the top face of the cylinder with the Knit Surface.
9. Full Surface Model
Probably overkill, but you can construction the whole thing out of surfaces, using a single sketch. Create the angled plane and a bottom plane, project the geometry and create two planar and one extruded face. Trim and knit the whole thing into a solid.
10. Polygon without Pattern
You don't have to use a pattern, if you extrude a polygon with 80 degree draft (though a polygon is a sketch pattern). Create a plane at the top vertex, convert the polygon edges onto it, then Extrude>Offset from the bottom face to the bottom of the drafted polygon. Use a circle (the Polygon circle) to cut the excess material.
11. Loft
I would not loft this, but you could. The initial problem I faced that projecting the bottom segment sketch onto the loft happens normally, so they don't align. Instead create a segment surface tube, create intersection curves on the bottom and top plane, then use the intersection curves to loft between. One step not shown is the "Cut-OutsideFace" that was necessary, because the loft did not merge into a single surface on the outside. So, extrude a slightly bigger loft and trim back.
12. Toolbody Combine with Subtract
Another relatively simple approach is to use a toolbody and extrude cut the drafted polygon from option 10. Use a move body to align the toolbox vertex with the top of the cylinder, then Combine>Subtract the yellow toolbody from the blue cylinder.