Surfacing help

[Gemnoc]

I've always used SE for modeling metal profiles and sheetmetal.

I'm a little out of my depth here.

I'm trying to model a shape that's like a water drop (or an egg) cut in half.

How would I go about it?

I'm unable to make anything with a sweep. It tells me geometry is self-intersecting.

Am I wrong assuming that for a surface sweep, the path cannot touch both ends of a profile?

Solidworks' sweep feature seems more powerful. If you'll look at this spoon modeled in SW, the guide curve touches both ends of the path. Is there a way to accomplish this in SE?

Any help will be greatly appreciated!

BTW Matt Lombard's blog is really an interesting read. It's a pity he's on Solidworks!

 

[donyoung]

Hi,

something like this one? It's based on an eliptical sketch
converted to a curve and then put into shape. Volume as well
as surface body included (V20)

dy

 

[Gemnoc]

Thanks Don,

Sorry for not getting back earlier. This project is having me jump through hoops.

I'll say this, you truly are a "quick person". Quick to find a solution, quick to act on it.

I wouldn't have though of a revolve. Doh! But I'll file it for future reference, because unfortunately, I wasn't clear in my description. The shape is actually squished and can't be revolved.

Here's what I did for now. Two revolved surfaces of curves, and joined together with other sweeps. It doesn't satisfy me because even when the four different surfaces are stitched, the joint lines stay there...

 

[donyoung]

oh yes, that's quite different. Hmm, what about using BlueSurf?
Unfortunately I've done only very simple things with that function
so my experience is rather low on this -- it's not that easy to
master ...

dy

 

[Gemnoc]

Hi Don,

Yeah, I tried to play with BlueSurf. I can make a few paths and cross-sections, but I have no way to get the shape (contour) that I want on the base plane.

I haven't gotten back on that part yet, working on something else at the moment.

The local VAR offers 2-day courses on surfacing, but they need to have enough registrations for it - and I need the knowledge yesterday! (this piece is about the simplest I have to work with) Oh well...

 

[Gemnoc]

To continue on the subject of sweeps.

I'm having a hard time with modifying paths or cross-section. With any other tool in SE (extrude, cut, revolve, etc.) I can delete a profile and draw a new one for a given feature, and the feature will update without trouble.

I'm unable to do that with a sweep, be it a solid or surface feature. I've tried, and I can't find a way to select a new path or cross-section. I end up having to delete the feature and do it again, which is a major PITA because a lot of features downstream then fail (I use sweeps early on to build the first body feature).

Why I need to make so many changes? Well I'm still at the conceptual stage and the customer wants to see multiple variations. But it takes forever if I have to practically rebuild the part all over again...

Am I doing it wrong, or the sweep feature is that unforgiving?

Thanks for your input.

 

[karmoh]

Hi Gemnoc,

There are some surfacing & bluesurf tutorials here

http://www.geocities.com/segurucool/

Although the site is dated you may find your answer.

 

[Gemnoc]

Hi karmoh,

Thanks for the link, I already found it posted by beachcomber in another thread.

I visited the site yesterday. There are many tutorials that I found useful, but I'd like to find more... It's very unfortunate that there are so few resources for SE, compared to any other MCAD program.

 

[karmoh]

It’s like any commodity, supply and demand!

I have a theory that Solid Edge is brought by Engineers for Engineers, hence they specialise in their own field and being real Engineers we find work-around methods and get by in our own little environments.

Other main stream Mcad products popular to masses are brought by Purchasing Departments, due to branding and sales pitches. Once introduced nobody has a clue hence the mass of literature and video tutorials (supply and demand).

With the advent of ST, if the branding is correct and the sales pitch honed there will be a glut of tutorials for ST good and bad. Because to be honest to an untrained eye a demo of ST looks really cool and unsuspecting Purchasing Departments will be hooked. Which if I suspect correctly is where Siemens want to be, grab a sale and walk-on-by

 

[Gemnoc]

Hehehe.

It's a good theory in regard to ST.

I have my own on SE in general.

SE is not as widely known as its arch-rival, SW. The last one is more tought (as in teach? not sure of the correct tense) in technical colleges and universities. At least that's the case, here in eastern, french-speaking Canada. That's why you can find so many SW books and so few for SE.

As for surfacing, I guess SE is mostly used for machine design and less for consumer product design. The tools are there, it's just that not many use them. Or they don't visit Eng-Tips!

 

[Gemnoc]

After reading a few tutorials on SeguruCool and fiddling with the software, it seems that Don was right, BlueSurf is the way to go.

It's versatile and seems to generate better surfaces than the sweep command. It can also make lofts. Maybe that's why the loft command was left out from the Surfacing tab in the ST ribbon bar...

BTW Since Yahoo is closing GeoCities at an unspecified date later this year, I hope Segurucool's author moves its content elsewhere. It would be a pity if this unique SE content was lost, even if it's dated.

 

[kjoiner]

" Since Yahoo is closing GeoCities at an unspecified date later this year, I hope Segurucool's author moves its content elsewhere. It would be a pity if this unique SE content was lost, even if it's dated."

That would be shame if the content disappears. I have learned more (what little I know) about surfacing from the Segurucool site than from anything provided by Siemens or Solid Edge. If it looks like it will disappear for good, I may just have to print out the pages and keep them for reference.

Kyle

 

[HDS]

You should let him know you want him to do it.

 

[kjoiner]

I just sent an email to Tushar Suradkar letting him know how much we appreciate the site and we hope he will keep Segurucool running in the future.

Kyle

 

[cadman1964]

I never knew about this site. It looks interesting but like you said, lots of older stuff but yet useful. Maybe he should transfer it to Jason Newell site

http://www.jasonnewell.net/

Solid Edge V20

 

[beachcomber]

For this shape you can use bluesurf or a lofted solid.
Remember that a POINT can be used as one of the cross-sections.
The attached image shows how I created it - 2 profiles for the sweep paths and point-profile-profile-point for the cross-sections.
I just ceated 1/4, but you could do the whole thing in one go.

bc.
2.4GHz Core2 Quad, 4GB RAM,
Quadro FX4600.

 

[Gemnoc]

Thanks beachcomber,

I'll try your method, it looks nicer than what I did.

 

[beachcomber]

Hi Gemnoc,
The trick is to get tangencies where you want them.
It can involve a bit of construction with spline curves etc.
If you want a more detailed explanation of my construction let me know.


bc.
2.4GHz Core2 Quad, 4GB RAM,
Quadro FX4600.

 

[Gemnoc]

Hi Beachcomber,

I figured out how to constrain/dimension spline curves, if that's what you mean: making sure they start perpendicular from the base plane, ending tangent at the top.

Any other tip would be welcome. I might return to this component tomorrow.

Thanks!

P.S. Are these points at the ends, or bluedots?

 

[beachcomber]

Hi Gemnoc,
Yes that's the sort of thing I mean.
Sorry, I don't really have any other surfacing tips - when I do it it's often a case of trial and error to get the best shape.
I don't think SE has enough control over surfaces, but then it's never really targetted that area.
The end points are created from the Intersection Point command on the surfacing menu.

bc.
2.4GHz Core2 Quad, 4GB RAM,
Quadro FX4600.