Problems with an IGES conversion

[John Giess]

I was given an IGES file with 132 surfaces on it. I converted it using V9. I then converted the surfaces to a solid. I was getting a lot of errors doing this, but it finally made 1 solid. I put this solid on its own layer and I also had many invisible entities on another level. From another search I believe these are left over from the conversion to a solid and I should just put them on another level and blank them. Now I am getting strange things happening like when I create a bounding box it makes the box bigger then my one solid model on the screen. Also when I do a pocket operation it seems to put the toolpaths a few inches up from the top of my part, which is Z 0. It will machine the part but puts these extra cuts up from Z 0. Any suggestions as to what could be going on. I have little experience with IGES files but I didn’t think it would give me this many problems.

[Hardmill]

If the tools jumping up and down off your surface you

probably need to loosen up the gap settings.

 

 

PEACE

[Thad]

Personally, I would have just machined the surfaces. I see no need to create a solid.

 

When you backplot, zoom way in on the areas that machine above Z0. You'll probably find a tiny stray surface. If it doesn't matter, delete it.

 

Keep in mind that many refer to IGES as I-Guess.

 

Thad

[Thad]

Can you put the file on the FTP so we can have a look?

 

Thad

[John Giess]

Thanks Thad,

I took your advice and just machined the surfaces. I was able to machine the part with no problems. I have not used surfaces much for machining since I usually work and draw with solids. I need to do more work with surfaces- I guess there is not a big difference when machining with surfaces instead of a solid. From what I see it just how you need to select them.

[cadcam]

John you are fully correct.

[Teh Bear without Brains kinda idiot]

I prefer surfaces for Machining .

I prefer curves for geometry .

Solid geometry still buggy like solid chains for contours and points for drilling .

And I had some issues with boundary box

It can be noted ,that this is a problem of your Iges though ,it may have tons of small gaps and intercrossing .

In this case solid is an approximation with some tollerance .

++ before going to use solid better check it in analize ,if it healthy at all

Now ,generally ,if you do not use it for creating ,like making molds using boolian remove your making of solid is a waste of time and effort .

My prefered way of 3d toolpathes :

If I have solid ,I produce surfaces on a separate level .

Now ,I color drive surfaces one color ,check surfaces the other one and select them by color .

[cadcam]

Winnie works much better in Vx as I cut from them all the time.I found some of what you say in V9