How would you have modeled an equilateral pyramid?

[sprior913]

I've been using Fusion for a couple of years now and this weekend was caught by what I thought should have been very easy.  I wanted to model a pyramid shape for my son's math class that had the same length for every edge.  Here's how I ended up doing it.

I created a sketch and drew a triangle with dimensions on the 3 edges.  Then I drew lines from the center of each edge to the opposite point and found the center.  I then created an axis parallel to Z from that center point.  Then I created a construction plane through that axis intersecting one of the points.  I then created a sketch on that plane and drew a triangle with the edges being the axis to the tip of the base, a line along the axis, and a diagonal line with a coincident constraint to the axis line and a fixed dimension length.  So now I knew the height of the tip of the pyramid.  I created a construction plane parallel with the base at the tip.  Finally I used the Loft command to create the pyramid body starting with the original base triangle and ending at the point on the top construction plane.

This worked, but I was surprised it was that complicated - 2 sketches, 2 construction planes.  Can anyone think of a more efficient/better way of doing it?

[HughesTooling]

You can do it with a 3d sketch but it is a bit tricky getting Fusion to draw lines out of the sketch plane, you need to tilt the grid back and when you get the mouse in the right place you can draw a vertical line. You need to dimension the line as it's draw, you can't add it later. I projected in the Z axis then used a coincident constraint to the end of a vertical line. File's attached.

Mark

[JDMather]

2 2D sketches and Loft to Point will work even if the apex is skewed.

[sprior913]

Thanks, I started off thinking along those lines, but wasn't sure how to pull it off.  How do you then go from that 3D sketch to making it a body?

[HughesTooling]

@JDMather idea of loft to point is probably the easiest, you only need the base triangle and one of the edge lines rather than all three with this method. If all the faces are different you can use the patch workspace, create a patch for each face then stitch.

Mark

Edit, thinking about it a bit more, loft to point will work even if all the edge lengths are different.

[kb9ydn]

It will be SO nice when Fusion finally has proper dimensioning and constraining capability in 3D.

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