Hi guys,
I was wondering if there is a command that stretches the cone flat on the C plane.
the image was made by hand by me, it only serves to give an idea of what I would like to do.

With the "Unwrap curve" I believe that you can make that you want! ;)
Then Flow
Just to re-find the trick! :)

http://moi3d.com/forum/index.php?webtag=MOI&msg=5136.1

Hi Tony, some previous discusssion on unwrapping cones here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=6175.1

I think there is a plugin script (or maybe 2 of them) in that thread as well.

You can do it with some construction geometry as well I think . Get a line on the other side of your cone and then select that line and the edge of the cone to do a "mutual extend" so they meet at the apex point:





Then select that line and use Transform > Rotate > Rotate axis to rotate it so it's on the x/y plane, and that then becomes the radius of the outer circle on the unwrapped shape.

- Michael

An easy process :)
Take the edge of the cone
Copy somewhere - Oriente / Line-line/none on the XY plane
Ask détails of the base cone circular length : copy to the ClippBoard
Arc Circle Center on the extremity segment
Copy the clippBoard inside box length of the arc circle
Close to the edges
Plane
Surface Cone = 1260.781055 (don't forget to kill the base surface!!!
Surface simulated "unwraped" = 1260.781248 not so bad!

Will be the same for an horizontal truncated cone - just 2 arcs circles
the trick is to ask the details! :)



The asked detail!

Same technic
Make like the cone above and kill the top base circular...with the new arc and edge...



Not yet moment of inspiration for an inclined truncated one! :)

Hi guys, I tried both the script and making it by hand but I can't, I'm sure I'm wrong in something :(

Hi Tony,

re:
> Hi guys, I tried both the script and making it by hand but I can't, I'm sure I'm wrong in something :(

The lengths of your circles seem to match up ok, it looks like you made it ok. What is it that isn't right?

- Michael

Hi Michael, I have noticed that the two areas of the two items do not match

Hi Tony,

re:
> I have noticed that the two areas of the two items do not match

Well the surface area of your cone is: 503.22 and the surface area of your flattened one is 503.35 . So they are close to matching.

What is your construction process?

If you are copying a numeric length somewhere maybe you need to temporarily increase the number of decimal places that will be shown under Options > General > "Decimal display" to improve the accuracy.

- Michael

Hi Tony77,

Is this what you want?

-Psygorn

I followed Pilou's video but I must have made a little mistake

Hi Tony,

re:
> I followed Pilou's video but I must have made a little mistake

Does Pilou's steps involve copying a length value and using it somewhere else?

If so then before you do that step try setting Options > Genreal > "Decimal display" to the maximum 7 decimal places (1.0000000) so that you'll have more precision in your result.

- Michael

My method gives 503,2224539
Original cone is 503,2206188
best of Psygorn is 503,221746 so he wins by 0,000007! :)

Ok Michael I will follow your advice ;)