Extended Trim Surfaces

[Jimmy_2004]

Can anyone help on this one? I have a trimmed surface of a part and want to extend it by 0.100". I have used moldsplus, it doesn't work out properly. I have offset contour then created numerous sufaces, ruled, sweep, coons & nothing looks right, I have highlighted the extended surfaces, the yellow surace is the one I want to extend to blend with the blue ones. I have posted on the ftp as extended surfaces.mc9.

[Jimmy_2004]

Note. Its not on the FTP, I will put it on as soon as it is back up and running.

[Roger Peterson]

Jimmy, what did you try in moldplus, extend edge or edge offset. Edge offset with limited set to yes should work.

 

 

HTH

[billystein]

try to untrim the surface and then retrim or extend

[Rob Peirolo CNC Software]

Jimmy_2004,

Sometimes when you trim a surface, the original untrimmed surface gets automatically blanked.

Go to Screen, Blank, UnBlank and you can restore the original surface. I realize this is not extending your trimmed surface, but it gets you back to where you started from. Now you can copy the untrimmed surface to another level, re-blank the original. (just in case) and re-trim.

 

HTH

Rob

[Thad]

quote:

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Its not on the FTP, I will put it on as soon as it is back up and running.

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It's back up.

 

Thad

[mac1]

How do you untrim a surface? What if I didn't trim it, I got it that way. Catia must've made it that way? I'm trying to extend tool paths past the edge of the surface and can't extend the surface because "Cannot extend trimmed edge of trimmed surface" Can't find a way to "lead in" to sruface path.

[Steel Surgeon]

Sometimes when you untrim a surface you will end up with a can of worms, so be carefull.

 

I think its modify, surface, trim, untrim. or close to that. I am not at work so I can't remember menu but its close to this.

 

Good luck

[Glenn Bouman]

quote:

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Can't find a way to "lead in" to surface path.

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In your finish toolpath parameters "Gap Settings" dialog try setting the "tangential line length value"

 

This will extend the toolpath.

[Mike Whitten CAD/CAM Contractors]

Use can use "direction" to bring the tool down off of the material also.

 

Mike

[Thad]

I've had some success in adding (or subtracting) an offset value in the containment boundary settings.

 

Moldplus will allow you to extend a trimmed surface.

 

Hey Jimmy, we're still waiting on your file.

 

Thad

[JAMMAN]

As covered before many times, the best way seems to be to create curves along the edges of the surface, delete the surface, then re create it with the curves. Then it hasn't been trimmed any more and you can extend it by any amount you want.

 

Untrimming can be messy because it untrims all trimmed edges of the surface. It still may not be long enough at that point.

 

Trimming always leaves the original surface blanked, thats why the level manager says afterward there are more entitys than you can actually see and count. This is a feature I dislike and causes much confusion especially if you move trimmed surfaces to another level because the blanked ones stay on the creation level and show in the level manager as "ghost entitys" I call them.

[Thad]

quote:

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Trimming always leaves the original surface blanked

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Unless you change the settings to delete them.

 

Thad

[JAMMAN]

Thanks for the heads up, I'll look for that setting monday!

[Scrap Iron]

All,

To untrim a surface, use Create, Surface, Trim/Extend, Untrim, and select surface to untrim.

Stay away from the Backup button or Esc key until you are sure you got what you want, so Undo will be available if you don't like the results.

Also, make sure Dispose is set to K for Keep the original trimmed surface, you may need it for something later. Untrimming a surface simply unblanks the original untrimmed surface, if you imported a file, from Catia for example, this original surface is in the database somewhere, usually blanked out. Once you have the original surface restored, you can then trim it (or extend it) as needed. An original, untrimmed surface cannot be deleted unless you also delete all trimmed surfaces associated with it.

 

HTH,

 

Scrap Iron

[Thad]

quote:

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What if I didn't trim it, I got it that way.

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mac1,

 

All the trimming/untrimming suggestions are options in your case. It doesn't matter if you got it that way or you created it yourself.

 

Thad

[mac1]

Ok I untrimmed the surface and then was able to extend it. It looks close enough for the application.

What I'm understanding is that the only way to run a tool past all edges/boundries of surface is to extend the drive surface itself. Using gap settings I can only get the tool to run past 2 of the 4 sides.

Thanks

[Thad]

quote:

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Using gap settings I can only get the tool to run past 2 of the 4 sides.

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mac1,

 

I've wondered that myself. It appears the gap settings 'trick' only works on 2 of 4 sides.

 

See if this works for you. Make your containment boundary the size of your part (or slightly larger), and chose the option "inside" of your boundary. Then add an additional offset. For example, if you're using a 1" cutter, give an offset value of -.6. .5 of that will get you back to "center" and the extra .1 will be your extension. Try different values to suit. I'm not sure if the tool will "fall off" at the end or not. So far I've had good luck with it, but I've only used that method 3-4 times. Verify, backplot and use at your own risk.

 

Do you have Moldplus? It's so much easier that way!

 

Thad