Stitching Styling Features 2

[JuhaEdag]

I'm a Catia v5 user trying to pick up some UG. We're using Catia v5r16 and UG NX3.
One feature I'm trying to find (and I'm sure UG has it somewhere) is the ability to sew in e.g a styling blend fillet into the existing solid. The reason is that styling surfaces are not allowed to change and the fillet curvature is smaller than the thickness.
In v5 I would join the blend and trim the boundaries exactly to the solid and then use the function Sew (without intersection) and if the blend is perfect (which it usually is because it's a-class) it will insert the blend into the solid. On the B-side I would just put in a normal radius.
I do have the docs and I have done the cast training but haven't found any specific examples of this nature.
Any help is appreciated.

 

[Xwheelguy]

Either extract all the surfaces of the solid and trim them to the new blend and Sew the surfaces back into a solid or you'll have to use Patch, which is the better of the 2 options.

When using Patch, you have to completely enclose a volume (with part of the solid and the surfaces you wish to add) and have no holes/gaps between the surfaces and the solid. See the Documentation for a better understanding...difficult for me to explain it without visual references.

Tim Flater
Senior Designer
Enkei America, Inc.

http://www.enkei.com

 

[JuhaEdag]

Thanks! Patch surface was the equivalent (to v5 sewing) function I was looking for. The weird thing was that I had to make the blends solid for it to recognize the surfaces. In v5 I would only need the joined surface.

 

[Xwheelguy]

If the surfaces wouldn't patch, then there must have been gaps somewhere between the surfaces and the solid that shouldn't have been there. Patch will allow you to add surfaces to a solid if you have it set up correctly. If Patching an inside blend/radius, then the tangent edges of the blend surfaces must lie on the solid correctly for their full length, while the other 2 ends of the blend must extend up to the solid, preferably through the solid.

The documentation explains how to use Patch quite well. Without having your part on hand, it's difficult to know for sure why the blend surfaces wouldn't work without making them solid.

Tim Flater
Senior Designer
Enkei America, Inc.

http://www.enkei.com

 

[JuhaEdag]

Thank you very much it worked like a charm once I had trimmed the blend to exactly lie on the solid (the sewing was a little larger than my solid wouldn't have worked on v5 either my mistake) and I found the documentation as well.
It was definetly worth a star thanks again Tim.

Regards
Juha

 

[Xwheelguy]

Juha,

Good deal. Patch can be a very powerful tool for adding complex surfaces to an existing solid.

Tim Flater
Senior Designer
Enkei America, Inc.

http://www.enkei.com

 

[cowski]

If the surface is larger than the solid, couldn't you just use the surface to trim the solid? I'm not very familiar with patch so I was wondering if there is any advantage to using patch vs trimming. Or is this case of another way to skin the cat?

 

[Xwheelguy]

It's another way of skinning the cat, to an extent. I wasn't sure if he was removing or adding volume to the solid, so I took a guess and suggested using Patch, since it will work when adding or removing volume to a solid.

Sometimes Trim Body doesn't work when you have surface edges that lie exactly on the solid (non-manifold condition or tangency, etc.), so Patch is what I fall back on in this case. It can be a big time saver if you're stuck with trying to insert complex surfaces into a completed model.

In another situation, where you're adding volume rather than removing it, I'd say Patch is about the only thing that might work, without making the added surfaces into solids and Sewing (solids) or Uniting, which is just more mouse clicks.

Tim Flater
Senior Designer
Enkei America, Inc.

http://www.enkei.com

 

[cowski]

Thanks for the info, Tim - useful as always!

 

[Xwheelguy]

No problem cowski...glad to offer any help I can.

Tim Flater
Senior Designer
Enkei America, Inc.

http://www.enkei.com

 

[JuhaEdag]

I was removing material in this case a styling blend in a C-pillar trim. The styling blend had a curvature radii less than 2mm and the thk of the part is 2.5 so it wont offset (or hollow).
In Catia v4 and v5 when you use Patch (it's called sewing in Catia)it ensures that you keep tangency and curvature conditions intact but if you use a trim or subtract operation you might be able to remove the material but it could destroy the tangency-curvature condition hence that's why when doing the sewing the boundaries must lie exactly on the solid.
I suppose UG works in a similar way.