Rips or Tears in SW2006 Models

[Spurs]

I have had a few instances where the SW2006 model that I created (using a cavity process) has what would visually best be described as a tear in the model. What I mean by this is that when the model is viewed from a certain orientation - say from the front plane, you can actally see background lighting through tears in the model. When you view the same plane from the opposite side, these tears or holes are not there, nor should they be.

I have been told by a machine shop that when they go to cnc cut the part, the model does not come in clean in the area of the tears.

Has anyone seen this sort of thing before and can help to tell me how to prevent it?

 

[ctopher]

Can you show us a picture? Hard to imagine what you are looking at.

Chris
Systems Analyst, I.S.
SolidWorks 06 4.1/PDMWorks 06
AutoCAD 06
ctopher's home (updated 06-21-06)

 

[Spurs]

I have tried to take a jpg off the model, but the JPG does not show the hole like the model does.

The torn surface cannot be selected using the mouse.

The only reason why i know it exists is because when the model was read in on someone elses system, it is there as well.

Think of this particular model as a thick ring with an inner and an outer diameter. On one side the surface has been profiled using the cavity feature. The profile only goes about 10% thru the thickness of the ring.

When you view the profiled surface from above, you see the some areas where the backround is visible right thru the part. When you view the ring from the opposite flat side, no tears exist, and the flat surface looks fine.

 

[ctopher]

Don't save as jpg, do a screen shot "alt/print screen", then paste into paint or something else. Then save as jpg. It is hard to make an assumption without seeing what it looks like myself.

Chris
Systems Analyst, I.S.
SolidWorks 06 4.1/PDMWorks 06
AutoCAD 06
ctopher's home (updated 06-21-06)

 

[Heckler]

I have seen this on a couple of my prototype models and have imported them into MasterCAM v10 with no problem. It appears to be a visual thing. Try doing a cntl Q or rolling back the history tree one feature at a time.

Best Regards,

Heckler
Sr. Mechanical Engineer
SW2005 SP 5.0 & Pro/E 2001
Dell Precision 370
P4 3.6 GHz, 1GB RAM
XP Pro SP2.0
NVIDIA Quadro FX 1400
o
_`\(,_
(_)/ (_)

Never argue with an idiot. They'll bring you down to their level and beat you with experience every time.

 

[EEnd]

Try going to:
Tools -> Options -> Document Properties Tab -> Image Quality and bumping up the "Shaded and draft quality HLR/HLV resolution" slider.

Eric

 

[ctopher]

I agree with Heckler.
Are you creating it using surfacing?
I tried with doing some surfacing. If the surface is created a certain way and the light is right, it can create the illusion. But, because it is a surface, it can at times get imported into CAM. Sometimes you may need to thicken it.

Chris
Systems Analyst, I.S.
SolidWorks 06 4.1/PDMWorks 06
AutoCAD 06
ctopher's home (updated 06-21-06)

 

[Spurs]

Here are images of what I mean by the tears.

http://webgearservices.com/TornSurface.JPG

 

[Spurs]

This was create by first modeling a ring, and then using a cavity command with a tool positioned against the ring.

 

[Spurs]

Heckler Cntl Q doesnt fix it

EEnd - Bumping up shaded quality doesnt fix it

Ctopher - i am not using surfacing

I have noticed that when I save the file in step format, then reload it from step, the image looks good. However, I loose the tree.

Any other ideas?

 

[Diemaker1]

I’ve seen imported models with invisible, non-selectable surfaces too… I say invisible because the part was solid, it would section, so the surface was there. I flexed a part once and got some invis-sufaces. But is that the problem? Or the heavily fractured surface? Did the mating part have all those pieces?

 

[dgowans]

Do you have a solid body in your part or is the part made up of one or more surfaces?

If you have a solid body, then the tear or hole is not there as far as SWX is concerned. It's more than likely a graphics thing which you are picking up visually. What are your graphic card specs?

If you have a solid body and your machine shop has issues with the translated model then it's a data translation issue. SWX may be creating geometry that it doesn't like to display correctly and the CAM software doesn't like at all.

Probably no easy answer to this one - data translation issues can be an absolute nightmare at times. Sorry.

 

[gwubs]

I've seen the same in my 2006 sp. 5.0 parts. Doesn't seem to be a problem other than visibly. Turning up image quality does not help either. Hope it's better in 2007.

 

[SBaugh]

As an example: If you have a body of a part that has a cut out into that just touchs the otherside you will get invisible surfaces. This is proven and a limitation presently.

So if you mad a box .5" deep and you made a cut that was .49999999 deep that thin little bit can show a transparent surface.

That doesn't look like what you are seeing, unless you have a cut-out behind what we are viewing in the jpeg file. Since it was molded, try andjusting the size a bit and see if it continues.

Regards,

Scott Baugh, CSWP

http://www.scottjbaugh.com

faq731-376

 

[Sneakers]

This looks like the same issue I see everyday. Knitting or combining complex surfaces or solid bodies will result in transparent faces. I finally reported this not long ago and got an SPR 335614 but I can't seem to look it up through the customer portal. Anyone else able to? I'll have to check with my VAR.

As a work around try a zero offset surface, delete the transparent face, then knit. Or do a split line across the transparent face...

Matt

 

[Spurs]

Scott

I am not cutting that deep into the solid ring. I have tried adjusting the thickness of the ring before the mold property is used - it doesnt seem to help.

The graphics card is on the tested and verified ok list.

 

[SBaugh]

The cut was just an Example.

if you have to bodies intersecting anyting that will cause a zero-thickness you will see this type of issue.

Regards,

Scott Baugh, CSWP

http://www.scottjbaugh.com

faq731-376