Failure after failure trying to create a funnel shape. Please, help! Thanks

[wisecad]

The best solution is a Revolution.

Is your thickness constant ? (the same thickness = only one dimension in the sketch)
The dimensions are for the interior or the exterior ?

Hi Shalmeneser. Thank you so much for your sample image. It truly illustrated the point you are making.
Certainly, a revolution would give you easier control over the thickness of the wall.
I guess based on the way I had conceived the walls they would have had constant thickness, but your image proved that if my implementation would have been successful my walls would have not been of constant thickness. For this design, precisely constant wall-thickness wasn’t high up on my concerns, but nonetheless a great point to keep in mind for my future and hopefully more sophisticated/refined designs. Thanks again.

[papyblaise]

if you want the funal "Castrol" famous in the garages, you start well, but you have to make the central loft before the pipe

[Shalmeneser]

Just one Pad and one AdditiveLoft (with 4 skectchs and option : ruled).

[chrisb]

Just one Pad and one AdditiveLoft

It is of course possible to use loft to create cylindrical shapes. But having a small number of features is not necessarily the best solution. The surface of a cylindrical loft is not the same as from a pad or revolve. You can verify if you try to refine two stacked lofted cylinders.

[wisecad]

if you want the funal "Castrol" famous in the garages, you start well, but you have to make the central loft before the pipe

Hello papyblaise, Thank you for your "Castrol" sample file. Very interesting!

[wisecad]

Just one Pad and one AdditiveLoft (with 4 skectchs and option : ruled).

Hello Shalmeneser. That is super-cool. Thanks

[wisecad]

Just one Pad and one AdditiveLoft

It is of course possible to use loft to create cylindrical shapes. But having a small number of features is not necessarily the best solution. The surface of a cylindrical loft is not the same as from a pad or revolve. You can verify if you try to refine two stacked lofted cylinders.

Hi chrisb
Good point about having a small number of features not necessarily being always the best solution.
Now, please pardon my ignorance, but what do you mean when you wrote that the surfaces are different? Isn't the final result the same geometrical construct (with the same properties) regardless of the path used to get there?
Also, what do you mean by "refine two stacked lofted cylinders"?

[chrisb]

Isn't the final result the same geometrical construct (with the same properties) regardless of the path used to get there?

No, it isn't. It is a similar difference as in 2D between a line defined by its two endpoints and a B-spline forming a straight line.

Also, what do you mean by "refine two stacked lofted cylinders"?

Make two lofted cylinders with the same diameter. Set Refine=True on the second loft -> there is still the seam.
Now do the same with cylinders created from two sketches containing circles -> the seam is gone.

[papyblaise]

it's like making the object with a mechanical latche or with a CNC milling machine
with the first one you will have a perfect cylinder, with the second one you will have an infinite number of facets
but for the Castrol which you like, my method is essential
i would like to see how chrisb would do it

[chrisb]

Here is the example I talked about. Note that in both bodies Refine is set to true.