Create curves from surfaces

[chas123]

How can I get a better wireframe from surfaces created in X. I've used mastercam since version 6 and never had a problem with this thru version 9. Switched to X and now have crappy splines when creating curves all edges.

 

Please advise...

[Colin Gilchrist]

If you are creating wireframe from surfaces and the surfaces themselves are poorly modeled, you will get crappy wireframe.

 

When you create curves on "all edges" Mastercam does just that, it creates dual wireframe on shared surface edges. This is because each edge independent of each other. The wireframe that is generated is dependent on how the surface was trimmed.

 

Your options are to create wireframe curves using the "one edge" method (basically only create the wireframe you need), or you can try and stich the surfaces into a solid. Once you have a solid model, the create curve on all edges should not create redundant wireframe...

[Verndog]

quote:

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How can I get a better wireframe from surfaces created in X.

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If the surfaces were created in X and quality has dropped (gaps), you may want to check your system tolerances and max surface deviation tolerance.

 

If you are looking for cleaner wire to chain toolpath I find I get cleaner planer wire by create / curve / slice then using edge curves (often times)...just be careful if the surface has angle to it because you get a wire (slice) at the Z level selected.

 

Also, the Chook SILHOUETTEBOUNDARY.DLL will get you the outbound profile, and can often be helpful.

[chas123]

Thanks guys, I appreciate your answers but these are things I already know and do! Back to the original question, why doesn't X create curves all edges of surfaces as accurately as version 9 and previous versions. To me this is annoying to have more steps than before. If I wanted 10 steps to do something I would use Catia!!! The best luck I've had is creating curves all edges in 9 then bring it into X for tp's. No inconsistencies and no screwed up chains for toolpaths. I've complained to Mastercam of this and it's still unresolved. They keep saying it will be updated in the next version! Yah right, we're at 4 now!!! Anyway, use mostly solid tp's now...

[gcode]

quote:

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why doesn't X

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what version are you using.. the initial release

of X in 2005 was very bad about this.

Its been fixed for several years though

[Thee Rickster ™]

quote:

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Its been fixed for several years though

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I started on X2 and I have redrawn many curves from

surfs, do to inelegant curves.

 

If I need tons of good ones.....

I export the surfs to another software and make good

curves, then import them to MC...many times.

[kkominiarek]

I am running into this issue right now. I import a model into MCX4 then create curves on the model. The curves DO NOT match the model.

 

I tightened up the tolerances/chordal deviation to .0001. (does not help)

 

One of our users still has V9 on his pc.....he imported the model then created curves...the curves matched the model perfectly.

 

Is there a fix for this yet???

[gcode]

Go to System Config/Cad Settings.

Look center right..

There is a dropdown labled

Spline/Surface creation type..

I have mine set on NURBS and don't

normally have any problem with bad curves.

There are 3 other options to try

if you are having trouble with a particular model

[mcpgmr]

What kind of surfaces? Don't you need a wire frame of some sort to create the surface? Perhaps create a Solid Model if you can and extract the surface then create the curves you need? I'm assuming your creating the surface because it can not be easily defined as a solid. I'm very limited with complex surface creation in MC. Now with Catia I did alot of land based turbine surface definition for designing 6 point nesting fixtures. Catia is built for that stuff. Not so sure about MC. Good luck!

[kkominiarek]

I got it to work.....

 

I set my "max surface deviation" to .0001(was .001).....curves match surfaces perfectly.

 

FYI - changing the "curve chordal deviation" from .001 to .0001 did not work.

[melliott6]

I have the same problem with creating wireframe from surfaces. If you can bring in a .stp file you will have MUCH better luck creating a wireframe from a solid.

[gcode]

I've found parasolids, (X_B or X_T) to be much more relieable than step files. Mastercam contains the UG parasolids kernal so parasolid

imports are more likely to be trouble free.

I have the most problems with models coming out

of ProE

[Josh T™]

quote:

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I have the most problems with models coming out

of ProE

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I've given up on anything but IGES files with the Wireframe checked from ProE. Even then you have to pay close attention to the system tolerance. Parasolids are ok but good luck getting a good wireframe from them.

[Thee Rickster ™]

I know only of one dude who seams to know how to

export any format out of Pro E. the other 20 i get

IGS as well.

[Metalmuncher]

Why not just use the native Pro E files? PRT

[Josh T™]

quote:

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Why not just use the native Pro E files? PRT

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but then you would have to buy a ProE Translator for MC and that's kinda like cheating!

 

[Metalmuncher]

Not if you got one

[MotorCityMinion]

"Parasolids are ok but good luck getting a good wireframe from them."

 

I've received many Para solids and create curves on import and they usually come out very accurate. If i get funky geo off a para solid, it's usually because it's a crappy model or multiple solids are present.

 

Side note: Anything I've ever made in SW, then saved as a Para Solid comes into MC with good wire geo.

[chas123]

All these things i have tried and here's another weird one. Go to SYS Config - SHADING - Chord Height (change to .00005). THis makes the surfaces look even better against curves, but end result still not as good as V9. If you don't believe ZOOM IN CLOSER! aha! I remember the days of a pocket having a perfect spline that you could chain and the days where you could select a line and arc partial,without having inconsistencies (in other words the days when the spline mated with the curve)...

[chas123]

Good Luck!

[MotorCityMinion]

Shading chord height is only relevant as eye candy. It has no bearing on the actual shape of the model or any of the actual tool paths. The only thing that actually takes place at .00005 shade settings is that your CAM package will run slower as it needs to put more resources into making the model look pretty.

 

"in other words the days when the spline mated with the curve..."

 

LOL, that happens everyday with the majority of the work I do. Sounds like the model may be funky.

[Mr Ray]

New guy on the block.

Does anyone have the ProE translator and does it work?

[crazy^millman]

If you have X4 you got one.

 

Welcome to the forum.

 

If you do not have X4 then you need to contact your dealer to get codes so you can get the translator.

 

HTH

[Dan@home]

Doesn't this cost extra? I see it in X4 and I don't have any pro e files at home to see if it works. If I remember it was pertty pricy.

 

Dan.

[John Summers]

One way to get curves that lie on the surface is with a flowline toolpath. In 3 axis, use the smallest cutter the system will accept. In 5-axis, any cutter, TIP, control comp. OFF.