Some more surfacing advice 2

[SiW979]

Hello all, long time no see.

If any one could give me some advice as to whether I have utilsed the best possible features/methods to achieve the highest quality surface and transitions between surfaces for the attached part I would be most grateful.

The two features in question are the last 2 in the tree. If you spot any more potential dodgy areas, then I would love to know better approaches to take.

Many thanks in advance.


Best regards

Simon (NX4.0.4.2 MP9 - TCEng 9.1.3.6.c)

http://www.jcb.com

Life shouldn't be measured by the number of breaths you take, but by the number of times when it's taken away...

 

[JohnRBaker]

First thing I have to say is that your excavating equipment is starting to take on a more visually pleasing appearance ;-)

As for the surfaces of interest, they actually look quite good although I did notice something which may not be what you were trying to accomplish. Look at the image below (with the last surface suppressed and note the areas circled in Red. It appears that there is a slight 'dip' in the top edges of the vertical surfaces. Certainly that edge is not even C1 continuous. Now I have to admit, I can't see where this is causing any adverse effect on the other surfaces, but it may still be something that you may wish to investigate.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.

 

[hudson888]

Simon,

Have a look at the attached. I've done it in NX-5 can you deal with that? I only noted that you were still on NX-4 belatedly. Nothing in the construction relies on features or methods that wouldn't have been available in NX-3.

Now what you really do have to understand about this is that surfaces always have four sides if they're to be any good for anything whatsoever. Some of your curves weren't usable either although they appeared continuous it was obvious when I tried to use them for surface construction that things improved when they were rebuilt. As for the edges that John mentioned weren't continuous I found that trimming either end of the surface would suffice to be able to create a reasonable result. Ideally I may have built to continuity without trimming, but in this case why rebuild the whole model if you can get a result by other means.

Obviously you'll need to analyse the data very carefully to pick up everything that was done and I can't emphasise planning thoroughly enough. I've put things on layers and used associative features more than I might ordinarily do so that you can perhaps better unravel the problem solving strategy that arrived at my solution.

Best Regards

Hudson

www.jamb.com.au

Nil Desperandum illegitimi non carborundum

 

[SiW979]

John/Hudson

Thankyou for your replies, I must admit John, I had not noticed what you pointed out there, I'm over in the US a couple of times soon, starting on the 5th July to the 19th, only the opposite side to you I think in Savannah, we've just moved a product line out there and taken on 15 ex CAT and Gulfstream guys who need to be trained NX and TCEng, perhaps I'll nip over to CA for a coffee, can't be that far! ;-)

Hudson, your method has flicked a switch in my head, so thank you for that, however, I can't help but notice that the output surfaces on your effort (I have NX 4,5,6 so it wasn't problem for me to open) are quite lumpy round the tight corner as shown in the attached image. What would cause this and how could I fix it?

Best regards

Simon (NX4.0.4.2 MP9 - TCEng 9.1.3.6.c)

http://www.jcb.com

Life shouldn't be measured by the number of breaths you take, but by the number of times when it's taken away...

 

[hudson888]

Simon,

I was honestly more concerned to convey the construction method than the result. You'd probably do better as you go further and lower around the corner cutting more into the original slab in order to have a more progressive lead in to the continuity. However in the attached with all the analysis tools on I can see some improvement just by adjusting the curve rebuild settings for the studio surfaces. More importantly I rebuilt the edge curves to simplify and smooth them. It wasn't necessary to show the construction but at least now you'll be able to see how important good curves are.

I've also turned on some analysis tools just so that you can see more closely for yourself what the surfaces really look like. At some point I think you'll almost always find some imperfections, but knowing when you have a good enough result is a skill to be learned. This isn't like sketching where you can expect it to be 100% because it is constrained properly, so you often need to use several analysis tools to satisfy yourself of the result.

Best Regards

Hudson

www.jamb.com.au

Nil Desperandum illegitimi non carborundum

 

[JohnRBaker]

Simon,

You're going to love Savannah. While you're there, make it a point to go out to Hilton Head Island. I assure you that you will find nothing like that in the British Isles ;-) As for "nipping over to CA", it's about 6 hours away (via fast jet), but if you actually do manage that trick, let us know and we'll stand you to a cold one or two.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.