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ccw
04-08-2007, 11:49 AM
Im not sure about this cut.
I had posted last week regarding the slice feature.
I think I don't have the resolution set up right or maybe I do.
My setup was using a .500 2 flute cutter@ 2.5 cle.end mill
I set the step over to 12% feed rate @5.60 and 18000 rpm on the spindle.
I cant help but think there is better quality cut and im not getting it.
Any suggestions would be greatly appreciated

5086


5087

Brady Watson
04-08-2007, 12:24 PM
Mark,
Your problem has nothing to do with the machine itself, rather it has to do with the quality (or lack there of) of the vectors that define the 3D machining boundaries & the 3D strategy itself. The grouped vector that comes in with each sliced RLF is pretty much junk. Delete it & re-wrap the vectors doing a greyscale from RLF, then select the yellow color and wrap vector to color boundary. This will in most cases give you a much better boundary vector than the one that came in with the RLF. In many cases this will reduce some of the jaggies around the boundary of each relief.

Furthermore, depending on the shape of the part, you might want to reduce your stepover distance to prevent the appearance of 'cusp marks' where there are compound curves, like the areas that you show above. You are going to get these types of marks depending on the shape of the part, regardless of whether you use ArtCAM, Cut3D or MillWizard (etc)...It happens & you are not doing anything wrong.

-B

ccw
04-08-2007, 01:21 PM
Thanks Brady
Im sure glad you are around today, I was sweating this and have a Monday delivery,Would you be willing to take a look at my file?
I am not sure I can do what it is you suggest.
Im being provided the art work and im not sure I know how to go about editing it?
Mark

Brady Watson
04-08-2007, 02:00 PM
Mark,
You can e-mail me the .ART or RLF & I will take a look at it.

-B

fleinbach
04-08-2007, 03:39 PM
Brady,

I will be making a sliced relief very soon and while playing with it I also noticed the sliced vectors become very Jagged. Deleting them is the easy part. When you say "then select the yellow color and wrap vector to color boundry" just how do you do that. I can select yellow at the bottom of the page but I have no idea what to do next.

Brady Watson
04-08-2007, 04:21 PM
Frank et al,
It is important that before you do this that you haven't attempted to toolpath the part yet. If you have, it moves the relief in relation to the material and you MUST do the following in order for things to turn out, IF you toolpathed the design already. Do it in this order (if not skip ahead):

1) Delete ALL toolpaths.
2) Delete material (icon in TP toolbox)
3) Goto Model->Set Postion and set Z position back to 0

1st thing you need to do is go to Model->Greyscale from Relief. This will show you a greyscale representation of the relief in the 2D view. This is NOT the green screen...

Then double-click on the yellow on the bitmap view (the greyscale that you just created) & then close the Shape Editor when it comes up.

Then go to Vector->Fit vectors to color boundary. In the 2 boxes on the screen enter a value of 1 and 1. Click OK. This will wrap vectors around the boundary of the YELLOW portions. Delete the vector that goes around the perimeter of the screen.

Keep in mind that depending on the pixel resolution of the model that, the vectors may appear to be too jagged. You can bump up the tolerance from 1 to something higher or start out with a higher resolution model. The higher the res used when INITIALLY creating the relief, the better the wrap will be. You can also smooth out some of the jaggies by using the spline vectors tool and setting an appropriate tolerance. I like to set my models to a minimum of 2000 pixels on the large side of the model for most 3D things, higher if I need the resolution to capture fine detail...remember, the higher the res, the longer things take in the software. I *believe* that each pixel is 8 bytes of memory...

That's the general jist of it...of course a video would be better & there will be one as soon as I get all the other projects out of the way!!!

Hope that helps!
-B

fleinbach
04-08-2007, 06:03 PM
Great, thanks Brady

I got it to work as you stated but so far the redraw was as bad as the original, with all jagged edges but at least I can play with it some now.

ccw
04-08-2007, 06:35 PM
Thank you again for your help. i will try to pick it out myself. if not i will drop you the file.
Mark

Brady Watson
04-08-2007, 10:04 PM
Frank,
"The higher the res used when INITIALLY creating the relief, the better the wrap will be."

So...if the original RLF was done with a low pixel count, you will get more jaggies than if it was done at a higher pixel resolution. In some cases it is worth it to redo the RLF in a higher res & then slice it again. This eliminates or greatly reduces the amount of node editing/tweaking that needs to be done.

When doing slices you really want to have a decent resolution set to ensure that the boundary where the slice meets the previous slice is clean. ALSO people...when you slice, you should already have IN HAND the material that you are going to use so that you can get your slices EXACTLY the right thickness so that it all matches up when it comes time to assemble. Accuracy and careful prep pays in spades.

-B