Another solution :)
(the 2 lines are of course drawn with the Helper lines for have Tangencency ;)


Not so a big deal ;)
ps Else this function exist in Google Sketchup ;)
Smartpushpull ;)
http://forums.sketchucation.com/viewtopic.php?f=323&t=23341

With the Michael's solution you must calculate the height before and the wight of offset ;)

Hi Pilou, that's an interesting solution!

But just keep in mind that offset and scale are not equivalent - offset will keep an even distance between 2 shapes, which can often involve changing the proportion of different internal segments.

For example if you have a curve like this:




Then offset will produce a result like this:




Notice how it is much differently shaped than just a uniform scaling of the original shape?

This is why you usually want to use offset and not just simple scaling in order to maintain an even "wall thickness" between pieces.

The only way that scaling gives you the same result is in some special symmetrical cases like a circle.

- Michael

Yes Scaling is homothetic (when x,y,z), Offset not ;)

So maybe Offset with my pyramydal concave convex form don't work due the different incline angles ;)

Tnx for the support! :)

I have a series of this type of the object!

See attachment! ;)

Tnx in advance!

p.s.
this is a simply view!

Hi MrBraun, it looks like your shape is made up of 2 different pieces - the little sharp point does not go to the same height as the pyramid.

So that means that you will be actually building it in 2 different pieces and then combining them together at the end.

So first construct the main pyramid body, by steps like this - first draw the rectangle:



Then select it and run Construct > Offset to generate the inner shape:



Drag the inner shape upwards in z to your desired height. If you know a specific numeric height you want to have it at, type that height in and press Enter immediately before doing the drag and it will set "Distance constraint" active for the drag so that it snaps to that height:



Now select both profiles and run Construct > Loft to build the main pyramid base shape:



Now for the smaller shape you repeat the same steps but at a shorter height. Here I used Draw curve > Polygon to make a polygon balanced around the midpoint, and then turned on control points for it and dragged the right points to the side:



Now repeat the same steps as before but with a shorter height:







Now those 2 solids can be selected and combined together with Boolean union.

- Michael

Tnx Michael for the precious and precise support! :)

Have a good day! ;)