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Author Topic: Accurate carvings without jerky motion?  (Read 962 times)

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Accurate carvings without jerky motion?
« on: April 11, 2018, 03:42:12 PM »
Hello All,
At my shop we carve pieces that need to be as detailed in accuracy as can be, as we do relief carving of a custom nature. So for the past few years my company has been using a Chinese made IG CNC with Mach3, and it has performed wonderfully. We used it for a production of a specific item, but that item was recently discontinued. So we have now set it up to do relief carving, but it has trouble on highly detailed carvings. The carves of trees we have done come out looking like they are "melting", everything is just smoothed off and somewhat too ugly for us to use. When we turn on the constant velocity Dist. Tolerance it causes our machine to jerk somewhat violently. I was wondering if their was a way to get our machine to carve accurate, without a massive amount of jerk in the motion?

P.S. I am new to Mach3, i am familiar with older Precix and Multicam but we are upgrading to more modern machines, so i know a good bit about it but not enough. Our precix and multicam machines carve the exact same relief with high accuracy and detail. I know the newer IG with better motors, VFD's, Smoothstepper motion card, and top of the line servo packs should be the Hero of our shop, but i just havent been able to get it to that yet. Any help is appreciated. Any questions about the machine or our Mach3 setup i will gladly share. Thanks all!

Offline ger21

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Re: Accurate carvings without jerky motion?
« Reply #1 on: April 11, 2018, 09:02:00 PM »
The best thing to do is turn on CV mode, but turn off all CV options. To get rid of the rounding, or minimize it, increase the acceleration as high as possible.

Unfortunately, there's really no way to specify an error tolerance with Mach3's trajectory planner, so if the acceleration isn't high enough, you'll get rounding, But on the other hand, the higher the accel, the jerkier it becomes.

Decreasing the feedrate is probably the best fix, but may result in really long cut times.
Gerry

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Re: Accurate carvings without jerky motion?
« Reply #2 on: April 16, 2018, 02:41:18 PM »
OK Thank you, i can give turning up the acceleration a try. Appreciate the help!