Stepover lines?

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rtibbs
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Stepover lines?

Post by rtibbs »

IMG_0721post.jpg

I know it's a lousy picture however, it's the best angle I could get to capture what I'm questioning.
On the final 3D finish pass I am getting a section several pass widths wide which are cutting slightly deeper than the rest.
They are very noticeable to the naked eye and the 'fingernail' test
Not sure what is causing this however, I'm "assuming" it's machine related.

Still learnin'

Ron

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TReischl
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Re: Stepover lines?

Post by TReischl »

Maybe, maybe not.

I used to get that quite a bit when I would use models that were exported from another program as bitmap files (bmp). The grayscale would look perfect coming out of Corel but when converted into a model, there they were. Never did figure out what exactly was causing it. Some of the experts here (Randy Newcomb IIRC) advised me to use a .tiff format instead. That helped quite a bit.
"If you see a good fight, get in it." Dr. Vernon Johns

wb9tpg
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Re: Stepover lines?

Post by wb9tpg »

rtibbs2018 wrote:
IMG_0721post.jpg
I'm "assuming" it's machine related.

Still learnin'

Ron
I'd agree and look at tramming your machine
Gary Mitchell
Kentucky, USA

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scottp55
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Re: Stepover lines?

Post by scottp55 »

Any possibility you were leaning on the machine at that particular point to inspect the cut?
Somebody posted once, and turns out that what it was :)
scott
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ger21
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Re: Stepover lines?

Post by ger21 »

Tramming won't fix that. It's mostly likely a loose coupler or something similar, where it moved a little one way, then moved back to where it was.
Gerry - http://www.thecncwoodworker.com

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Re: Stepover lines?

Post by 4DThinker »

Depending on how the toolpath was set up, it could be that after clearing an area the board may have bowed up. When the bit comes back to clear an area it previously skipped for efficiency it cuts relatively deeper even though to the CNC it was cutting perfectly as programmed. I've had exactly this happen when cutting 3D surfaces that cover most of a board. Wood moves.

4D

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TReischl
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Re: Stepover lines?

Post by TReischl »

What all these posts indicate is that there is a lot of things that have to be right or else. . . . . grrrrr.
"If you see a good fight, get in it." Dr. Vernon Johns

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rtibbs
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Re: Stepover lines?

Post by rtibbs »

Thanks guy's,
lots to consider.
Everything seems to be right and tight, not leaning on machine.
These are D&M files with one exception that was an imported .obj file combined with a Vectric clipart plaque. so I would hope they are not the issue.

It's not the first time it's happened.


Unfortunately, I believe it comes down to "You get what you pay for" :mrgreen:
May be time to upgrade my machine as I purchased this one to see if CNC'ing was something I'd be interested in continuing...….It is :mrgreen:
I guess I could always stick with 2D but what's to fun in that!

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