the last dinosaur

[thorst]

Alcides, I'm using an old version of Malz++Kassner CAD Economy (think it's version 4.7) which I found for 5€. It's a very intuitive 2D-CAD program in which I'm doing all my design work. The finished parts were exported as emf and colored in Inkscape.

For the spiral, look at this picture:

The circle sector which forms the cone was devided into 16 identical subsectors, and the distance between the starting-and endpoint into 16*(number of turns) segments with identical length. Through every of those points, a concentric circle was drawn like you see above. This all gives you a grid, and you now have to connect two diagonal neighbouring points with a spline (or another curve).
It may sound complicated, but the result is what you want: A curve which goes with constant speed towards the nosetip (the difference in length-coordinate is constant for the same angles). I hope this wasn't too complicated to understand...

Best regards,
Thorsten

[Alcides]

No, no. The explanation is clear. Thanks for that thort.

[KCinKC46]

If I can figure Sketchup out, I'll try doing this one as well as the new one and the assault type from UC.