reducing "stepping" on sides

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adze_cnc
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Re: reducing "stepping" on sides

Post by adze_cnc »

letterman7 wrote:I design in CorelDraw, the image was created as a vector initially at size, then converted to a bitmap through Corel.
If the vector file is "at size" (1:1 scale) and you altered the bitmap file to 600dpi I'd expect the bitmap to now have around 16,200 lines, which is a really huge file. But that should also give a 100% line-spacing of 0.0016 inches (read 16 ten-thousandths).

Steven

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Re: reducing "stepping" on sides

Post by letterman7 »

That's correct, and yet the preview image still shows stepping. As mentioned, the file as cut was at 300dpi, by your reckoning around 13K lines (not quite sure how you figure that Steven), and still the steps persist, even at 10% line space.

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Re: reducing "stepping" on sides

Post by Adrian »

As far as I'm aware from what I remember of posts in the past it's the number of grey levels that is the constraining factor. The DPI settings doesn't change that.

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Re: reducing "stepping" on sides

Post by letterman7 »

That's interesting Adrian. Since my program constrains to an 8-bit resolution that makes sense. Hmmmm... how to get around that....

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Re: reducing "stepping" on sides

Post by FixitMike »

I am confused!

The photo examples in this thread appear to be the carving of a 3D model such as one made in Aspire or imported into VCarve. But PhotoVCarve produces toolpaths for linear halftones. Can someone please explain to me what is happening?
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Re: reducing "stepping" on sides

Post by Rcnewcomb »

Mike,
PhotoVcarve treats special grayscale height maps images similar to how VCarve and Aspire handle STL file objects. Aspire can also use grayscale images. The level of gray defines the depth of cut. These files can be used by certain lasers for 3D cutting. Gantry Company makes these types of files.
Image

Regarding the cleaning up of the stepping, the best solution would be to do the cleanup using 2D vectors, so another package in addition to PhotoVcarve would be required.
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Re: reducing "stepping" on sides

Post by FixitMike »

Rcnewcomb wrote:Mike,
PhotoVcarve treats special grayscale height maps images similar to how VCarve and Aspire handle STL file objects.
Thank you. I read the entire help document and could not find any mention of PVC being able to do this. But then I went to the Vectric site and the program description does mention the capabilities.

I couldn't find a tutorial that says how to do this. Does one simply open a .stl file for this to happen? Or does it happen automatically when a STL file is opened? My version of PVC (1.102) doesn't seem to have the capability of opening an STL file. Click and dragging an STL file to the PVC icon doesn't work. And the HELP menu doesn't have any provision to check for updates.

Note: I have VCarve Pro 8.511, so I can do 3D from STL files. I'm just trying to figure out why I am unable to see all of the capabilities of PVC.
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Re: reducing "stepping" on sides

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Re: reducing "stepping" on sides

Post by FixitMike »

Thanks Adrian.

I do believe that Vectric should add this information to the PVC help document. And add a tutorial.

I strongly suspect that if I was ignorant of these capabilities, and couldn't figure out how to do them from the documentation, others will have the problem, too.
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Re: reducing "stepping" on sides

Post by letterman7 »

Randall,
Yes, I agree a vector toolpath will clean up the edges, but aforementioned, doing so would almost be impossible due to the rise and fall of the greyscale bitmap. I would be adding a single plane cut where I don't want one, so at this point only hand finishing will work. I will investigate a higher "resolution" greyscale - not a dpi setting per se, but possibly something that can be programmed within the software to maximize the number of layers of grey. That might lead to a smoother outcome.. we'll see - one more to do and I just got my foam delivered today. The weekend might be dusty :lol:

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