How to make a cone with a line as the apex

g10338905 · 1 Nov 2011, 03:40

I am designing cosmetic containers and having trouble making tubes such as for toothpaste and other creams (see attachment). The body of such tubes has a circular base and a line as the apex (I'm not sure what the geometric term for this shape is. Some kind of cone?).

The way I have been making this shape is as follows:

Draw a circle
Push to a cylinder
Scale the top circle into the thinnest ellipse possible in order to make a "line"
Scale the the thin ellipse in the other direction in order to stretch the tube to the right width

This is okay, but ideally I would like to have a single line at the top rather than a very thin ellipse.

Is there a way to do that?

Gaieus · 1 Nov 2011, 08:14

Maybe with the Curviloft plugin... (TIG has some other lofting tools, too)

http://forums.sketchucation.com/viewtopic.php?t=28586

Jean Lemire · 1 Nov 2011, 13:30

Hi folks.

See all scenes of the attached SU file for ideas.

Tube for paste.skp

g10338905 · 2 Nov 2011, 04:23

I tried Jean and Gaieus's solutions and both are better than what I was doing. Thanks.

After constructing the tube, I put a label on it. I have been doing this by projecting an image from a rectangle (see attachment).

Edit>Import>select image and import as texture
Position image on rectangle
Select Paint Bucket and click on image in the materials pallet
With Paint Bucket, right-click on image>Texture>Projected
Alt+click on image and then click on the tube

Is this the best way to put a label on the tube?

Gaieus · 2 Nov 2011, 09:55

Well, at least this is the easiest way (and the only one with native SU tools). You will notice that this planar projection creates a rather "ugly" distortion of the image on the sides of the round part of that tube. Now this is mostly only visible if your image goes all around - but in case of a "normal" tube (and what I generally see), the label itself is mostly only in the middle somewhat and then it should not be as apparent as now. There is a UVTools plugin that can do cylindircal and spherical projection:
http://forums.sketchucation.com/viewtopic.php?t=10404
and another one which can even "unfold" geometry and you can easily apply an image to the unfolded, flat mesh and then re-apply it on the tube:
http://forums.sketchucation.com/viewtopic.php?t=39442

Hussel Hann · 3 Mar 2012, 16:24

eventhough this post is quiet some time ago, i think it is a very good exercise for me.
below is my attempt to model a "tube"