Need Help!- Solid works

[dnelso]

Im having some problems with solid works files that have geometry above z-0
that should not be there. I have checked these files with rhino and alias and they show nothing.V23 and 21 show the same problem.
I am attaching a file that has these problems.
I have sent them to bobcad and they are looking at it. just wondering if anyone has seen the same problem.
Thanks

[SBC Cycle]

Originally Posted by dnelso Im having some problems with solid works files that have geometry above z-0 that should not be there. I have checked these files with rhino and alias and they show nothing.V23 and 21 show the same problem. I am attaching a file that has these problems. I have sent them to bobcad and they are looking at it. just wondering if anyone has seen the same problem. Thanks

I vaguely recall something about SW and verifying surface normals. I could be wrong but in your menu click on View - Surface Normal to make sure your normals are going the "right way". You may need to click View - Transparency to see all of them.

I might be way off here but there was something I remembered about it. Also, BobCAD's CAD module will also occasionally create surfaces that show above Z zero when you verify the entities even if you didn't draw them that way. Not sure what that's about.

EDIT: You can reverse the normal by going to Utilities - Reverse Surface Normal

[dnelso]

SBC,
I tried reverse normals with no luck. I was hoping you were on to something.These files are direct from SWorks not drawn in bobcad.
Thanks

[straz]

I looked at your post, but I couldn't find any SW file that you implied was attached. What version of SW?
PKS

[BurrMan]

This sounds like what you are seeing is "bounds data" and not geometry above zero.

More info would help.

So is what you are saying is you import a model that has geometry set at Z 0 and when you entity summary it is .0012 or something like that?

[dnelso]

Sorry here is the file. Tried both 2008 and 2009 and same problem

[dnelso]

Burrman,
I dont see geometry just entity summary shows as much as .25 above 0.
Then to do machine workyou have to lower part .25 below 0.
Thanks Dave

[BurrMan]

Yeah, I think this is bounds data. One way you can check it is to create a new layer and extract all the edges to it then hide the part layer and look again at the entity summary. I have 4 digits viewable so it then see's .0001. If you look in front view and zoom in on the upper left corner you will see where that edge rises above z a smidgeon.

The bounds data thing is most likely a tolerance setting in the other app that creates the issue. look in your other app for a tolerance setting and set it to something like .00001 then try to re-export the geometry to bobcad and see if it changes to a more true value.

[BurrMan]

BTW: Heres your part back slightly modified. It had some cracks in the surface.

If you extract the edges of this file the entity summary is Z=0

[dnelso]

I understand the extracted edges are at z0 but if you are doing 3d rough the part still needs to move down .1845 to machine. Is there a way to fix this or do i need to try tolerence settings in SW.
Thanks Dave

[BurrMan]

This is a question I never answered. Our fix was to up the tol settings in the creating app and get the proper value. I dont have solidworks so I couldnt test it for you and other apps settings didnt change it. I would try to see if solidworks can fix it with a tolerance change.

This question though has been in the back of my mind and I just spoke to a machine operator and set a test in motion. "For a 3d toolpath, does moving imported geometry down by the bounds data, or changing the top of part setting in the feature edit, change the surface toolpath and result in less of a cut?"

I'll post back the answer I come up with.

[dnelso]

Ok thanks.