Can't Decide On Surface Technique

[tlehnhaeuser]

attached is an image of a surface I trying to generate. Its much like a car hood scoop. But I can't seem to determine how to create this surface.

 

Any help would be appreciated.

thanks

Tom

[krowell]

There's lots of options from your starting point I think.

 

A cone and a cylinder are suggested by the outline, except for the spline curve on the backbone.

 

So I would go for a loft, as few as 3 profiles might do it.

 

Am I missing anything?

[Cary OConnor]

Can you attach the file? I need to see where the curve segments end. UV is the best but you would need to make that V a single continuous curve (add a small fillet at the V point).

Cary

[tlehnhaeuser]

Am I missing anything?

9344[/snapback]

 

 

Heith, The problem as I see with loft is "sides" are actual 2 3d curves and I need it to be 1.

 

I have attached file.

thanks

 

Scoop.ics

[Guest bkline]

Try This.

Hood_Scoop.ics

[tlehnhaeuser]

Thanks Bret,

I appreciate the file and it definitely provided some insght. Although I was looking to maintain the "sharp" corners and also hoping there was a way to "configure" an existing surface tool to create this surface.

 

I'm not sure how "Surfacing" modelers would create this, I'm not savvy in that area, but to the IronDUDES please consider this an ER. to add a surface tool to address this kind of need.

 

It appears to me that if I could use the EDGE SURFACE using 5 edges, It could be done.

 

Thanks

Tom

Edited March 14, 2005 by tlehnhaeuser

[Cary OConnor]

Hi Tom,

Here are two options. One maintains a smooth connection across the top (UV), however you need to add a smooth round in the front. The other is created using Two Guide Sweeps. You need to break up the curve along the back in two sections. I did this using a surface and trimming it (then create a curve from it). Take a look.

 

 

By the way...the curve in the back (in your original file did not meet at the endpoint of the base curve. This will cause you problems.).

 

Thanks,

Cary

 

Scoop.ics

Scoop2.ics

[Guest bkline]

I broke the loft into 2 shapes which retains the sharpness you want (I think).

 

I wish there was a option in the loft control the "weighting" of each section in the loft. Something like a slider bar that would control the tightness or looseness of the loft. 100 on the slider bar would create a loft with sharp corners, 1 would be very loose. This would give much more control over the transition in each section and eliminate the need to stack sections very close together to get a sharp corner. You really can model just about anything with lofts and I think they are much more efficient modeling technique that dealing with the current IC surfacing and 3D curves. Just my thoughts.

 

Bret

 

Hood_Scoop_Sharp.ics

[tlehnhaeuser]

Hi Cary.

Your approach 1 I guess is the best option. Looking at everyones files raises a few questions and ER's.

 

ER: I would be nice to have the scene browser indicate the type of surface used since I found it difficult to determine what surfaces were used if I didn't rely on your comments.

 

question: As for the UV Mesh. You have 2 "U"'s and 3" V's how did you know to make the "angle" curve a U or V. Is there a "anglular limit" at which point a cure is either consider a U or V or neither?

 

Thanks

Tom

 

[Cary OConnor]

As for the UV...It does not matter which order you pick the pairs.

Cary

[tlehnhaeuser]

OK,

I have another thats baffling me. Its basically like the tip of an elliptical bullet.

Any feedback would be appreciated.

Thanks

Tom

 

Scene2.ics

[cborer]

Cap from Ellipse is one of my ERs.

...as I remember this is not possible in IC.

I would try it as a loft shape.

[tlehnhaeuser]

Hi Carlo,

I tried as a loft shape but the only problem is the tip. I really need to define this shape with "true" arcs. Even if I could loft conceptually it still doesn't give me a perfect "tip".

Thnaks

Tom

[Cary OConnor]

Tom,

Can you reattach the file. I can't seem to download it.

Thanks

Cary

[tlehnhaeuser]

Cary here you go

Tom

 

Scene2.ics

 

 

PS: The arcs may not be touchng, this is for reference purposes.

Edited March 23, 2005 by tlehnhaeuser

[Cary OConnor]

Still can't download for some reason. Can you zip it?

Thanks.

Cary

[tlehnhaeuser]

Cary,

Hows this?

Tom

Scene2.zip

[Cary OConnor]

That works.

Thanks

Cary

[Cary OConnor]

Well I took a look at this and tried to think of a way to do it with surfaces. You could use a Spin with a rail but you cannot have the side profile (by the way we can't do this in IronCAD today). So the only other way I can think to do it is to break it into 4 surfaces using the sweep. Sweep with two profiles and one guide repeating it 4 time to close the shape. You will need to break the segments up to allow for this.

Thanks,

Cary

[tlehnhaeuser]

Thanks Cary,

I will take a look at trying it that way.

Tom