Weird movement when projecting toolpaths to molds

Weird movement when projecting toolpaths to molds

Postby frare bear » Mon Jan 30, 2017 5:59 pm

Hello!

I've been trying to cut simple shapes out of curved surfaces, and get poor cut quality most of the time.

To experiment, I've used different post processor's (arcs vs normal etc), I've run the same profile cut but NOT projected to the mold, I've slowed it down, I've simplified the vectors with circular arcs and bezier arcs, and tried cutting ON the vector instead of OUTSIDE the vector.

So far, the only combination that gives me any luck is ON the vector, and NOT projected onto the mold. I could get this to work to cut out the parts, but it would be faster and cleaner if I could cleanly map the toolpaths to the 3D shape.

Based off what I've seen, it seems Aspire is somehow coding things in a way that creates jerky motion, and low quality edge finish of parts. I've briefly looked through the shopbot code and don't see any real differences between a clean running code, and a jerky one.

Any ideas or help on this?
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Re: Weird movement when projecting toolpaths to molds

Postby Adrian » Mon Jan 30, 2017 6:13 pm

Without seeing the file it's hard to say...
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Re: Weird movement when projecting toolpaths to molds

Postby frare bear » Mon Jan 30, 2017 8:42 pm

Adrian wrote:Without seeing the file it's hard to say...


Here's an example of an unexplainably jerky file

And I added the smooth cutting file, with no Z movement
Attachments
Torus - cutout ARCS - circular.txt
Jerky movement along ~50% of the cut
(45.18 KiB) Downloaded 26 times
Profile 1 - on cut - smooth.txt
Smooth cuts, no z
(28.85 KiB) Downloaded 20 times
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Re: Weird movement when projecting toolpaths to molds

Postby Rcnewcomb » Mon Jan 30, 2017 8:59 pm

Can you post the Aspire file?
- Randall Newcomb
10 fingers in, 10 fingers out - another good day in the shop
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Re: Weird movement when projecting toolpaths to molds

Postby frare bear » Mon Jan 30, 2017 9:22 pm

We figured out what it was! Our Shopbot settings under VR (ramp speeds) needed a much higher "3D Ramp Threshold Setting" and a lower "Minimum Distance to Check"... essentially the MDC value was causing the machine to try and slow down at variations too small to matter, and ruining the piece. Now it ignores those tiny variations and stays at full speed

Thanks for your responsiveness!
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