Spoon bowl not evenly smooth

Still working on learning the nuances of CC Pro and 3D carving. This community has been extremely helpful. @WillAdams and many others have answered many questions and solved my issues so far. Here is the latest. The spoon is being carved from top left to bottom right in a diagonal pattern. No idea why but that’s not the issue. The issue is the “entrance” side of the bowl, the top, is very smooth but the “exit” side is not. You can see it in the picture. I have no idea what’s going on. Any help appreciated.

I used 1/4” end mill for rough tool path, 1/8” ball nose and 1/16” ball nose for finish passes. Step over for all is 10%.

How does the top of the stock relate to the top of the model?

How does this compare to the 3D preview?

Upload the file? (or send to me via PM again?)

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The 3D Finish path uses a lace / zig-zag / raster pattern, so every other pass has a stepover, then the next stepover is at the other end. So there are serrations left on the edge.
You can quite likely clean these up with a rough path that uses Z-level pattern, basically a series of pockets at different Z levels. Or a 2D contour path.
If you share the file, we can give you some recommendations.

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Top of stock and top of model are in same position if that’s what you mean. The 3D preview didn’t show any of these issues.

File is too big will PM to you.

File is too large to send you Will.

Please upload the file to a file sharing site and post the link here or in a PM or e-mail to support@carbide3d.com

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Depending on how long it took to do the run, i’ve had some success with doing 2 passes at opposite angles. So if this is a 3d finish pass and you have it set to 45 degrees for the angle, set it for -45 degrees, or even just 0 degrees, so that the bit is going back over and getting some of the little bits that are remaining.

Also, I’ve found that the smallest stepover you can tolerate helps. I’m doing stuff right now with a 1/8" ballnose bit and the stepover is set to 0.006". It takes forever but looks amazing!

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You can watch this. I am the youtuber :slight_smile: https://youtu.be/02U8FXtie20?si=8M0g0pwgriiQ2USH

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Thanks. File went to support per Will.

Thanks!

The Job Setup is:

and when we mouse over the 3D model we see that the height of the model is 0.5"

So while the model appearance is:

the 3D preview is:

which seems to match the cut.

If instead, the Stock Thickness is reduced to 0.5" to match the 3D model:

then the 3D model will be as expected:

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Will I know I can be dense, however how does this explain or resolve the issue I’m having with the finish carve not being smooth on both sides of the bowl? Sorry

You are carving a model which is only 0.5" thick which is within a stock which is 0.73" and are leaving 0.23" of thickness uncut.

If you instead use geometry which includes the surrounding area:

(Or increase the overall thickness of the 3D model to 0.23")

then the rounding will match at the top:

and the part will be revealed within the thicker stock:

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AH! I see now, thank you Will. I will give that a shot. Thank you!

Note that if your stock is actually 0.73" thick, the best practice will be to remove 0.115" from each side, then machine the final part.

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@Jmcwoodworking You could probably get away with one finishing pass as well. I’ve used 1/4 and 1/8 ballnose endmills with a 10% stepover on much smaller 3D projects and left no marks and no sanding required.

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Thanks @Jeffish you’re right. I was over compensating for my frustration and just trying anything. I will ratchet back. Thanks.

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Got it @WillAdams Thanks