Bad Solids from UG

[BIG DOG]

Hello All

I am having a problem, when machining a solid's from UG, it does not happen all the time but it happens enough to scrap a few steels.

I bring in parasolids made in UG, and am making toolpaths in Mastercam, and if the tolerance is too tight in the toolpath, (.002) the tool will fall thru the solid, because it cannot see a part of the solid. Some other times it will see a solid that is not there and will leave a lump, over the area, if I relax the tolerance to .003 it will machine fine.

A semi lace path with a 1.0 dia ball tool will machine great, But run the same path with a .75 ball, and a nose dive into the steel.

Some UG files are better than others.

Has any one else had issues with UG files?

[DC Gorn]

Sorry I do not use UG but I have used Parasolids from Proe and Solidworks and a few other programs and I have never seen what you are descriding. I have seen something simular from IGS files. One thing, Make sure you have the most up to date Mastercam and the converters.

[Thad]

Big Dog,

 

I know this doesn't answer your question, but if you backplot AND verify (compare to an STL), that should eliminate any scrapped parts.

 

BTW, I haven't seen this before with any file type.

 

Welcome to the forum!

 

Thad

[Mike Mattera - TFM]

Sounds like your bringing it in as surfaces and not Solids. Bring it in as a solids and there wont be any holes to fall thru.

 

Screen - Config - Toilerance - System Tolerance

What's this set to. Mine is .00005

This has to do with the tolerance of the surface (not the toolpath).

 

In your Toolpath paramneters: What is your Gap setting. Mine is 300%

 

Mike Mattera

[savagkd]

I gave up on importing UG or Ideas files. Way too many problems (intersections that aren't trimmed, holes between surfaces, etc.) Now they send me the wire frame and I create the solids.

It might be an IGES translation problem, I don't know. Can't get them to pay for a parasolid translator.

 

Keith

[Thad]

quote:

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Can't get them to pay for a parasolid translator.

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Isn't the parasolid translator "free" with MC?

 

Thad

[RandleXX]

I have ran into this UG solid issue before. One way I that I fixed it was to create a surface from solid and use that new surface in combination with the rest of the solid faces for the new toolpath.

 

Also, check surface "stock to leave", Gap settings and advance settings "edge, roll tool" will all make a difference in how the tool will react when it finds on of those mystery surfaces.

 

Hope this helps.

[BIG DOG]

Thanks for all the help.

I called up an old parasolid that gave me trouble. I changed my tolerance, gap settings, advanced settings, not any better.

I re-loaded the parasolid as surfaces, and it has a very bad trimmed surface that mastercam was avoiding, that did not show up as a solid.

It is a stinkin poor solid to start with.

If I import solids as surfaces, I can erase the bad surfaces and go on with toolpathing.

Thanks

[cadist]

Can you upload your any of problematic file with toolpath on ftp for other's to have a look. I am sure with that you will get some great tips.

[Greg Williams]

Big Dog,

 

No issues here, What version of UG are they modeling in, Are the files Sheets or solids

[Bill]

I have seen this happen with some UG files.

My way around was create surface from solid. After surfaces are created check surfaces, there are usually a few "bad" surfaces.

I have seen some surfaces created from the solid model that are less than .001 wide, which will drive MC processing crazy.

UG users use a lot of split body and [edit face]replace face to blend surfaces and if they pick planes with rectangular offsets they may be off a few tenths instead of the two lines they are blending to, you will get junk like that.

 

Also, if they use solid offset it can make some nasty little fillets depending on the offset distance to the original rad. size.

[BIG DOG]

I am glad to see that I am not the only one who has had issues with UG translation.

Not that I like to see others in the same pain as me, but to see that I am not alone with my bad solids.

I am making surfaces when importing a parasolid and am able to see the bad stuff, and delete it or replace it.

What I am doing is making 2 parasolid files from UG, an original file showing all the holes, pocket, and keyways. And another file that I supress everything but the shape. Overlay the files in mastercam on different layers and use the filled solid for 3-D toolpathing, and the wire frame original for 2-D work, pockets and holes.