At the Jleslie48's site there's a page that illuminated me, pushing me towards the adventure to design models using Microsoft Word as 2D CAD software. The results are kindly hosted by Jonathan at this site page (the Sprint and Hibex missiles). In the page at the first link there's also a link to a shroud calculator, useful for calculate a cone. Here some hint that Jonathan gave me "As far as techniques for microsoft word/draw goes, I've included my way of of getting the circle section. I basically do what you do, with the cover up shape, but I use the custom freeform tool to get it just right. I'm not sure what you mean by the angle thing, are you talking rotation of say a line? I don't do that. I overlay a right triangle onto the circle, and compute the height and length of the sides of the triangle based on the trigometric tangent, tan X = opposite side/attac hed side. so if I need a 37.65º angle say, on a circle whose radius is 50 mm, I would solve the equation: tan (37.65) = A/60 I use 60mm because I want the triangle to be bigger than the circle, so the height side of the triangle lies outside A = 60 * tan(37.65) the circle. A = 60 * 0.77149 A = 46.29mm. so I would build a right triangle with the dimensions 60 x 46.3mm, and put that point of the interior angle at the center of the circle. I'm sorta showing that in the file I attached." and here the attachement referred by Jonathan I hope that You can find useful my post. Enjoy, Nando