Need Help! Z height on second pass - help needed


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Thread: Z height on second pass - help needed

  1. #1
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    Default Z height on second pass - help needed

    Hi all,

    I have a problem hopefully someone can help. I'm relatively new to cnc and autocad and I'm having an issue. When I try running a toolpath on the machine, the first pass is perfect, but the second pass plunges too deep and jams the machine. Doesn't matter if it' s wood or aluminum. Granted it's just a tabletop axyz, but I think if I could get the machine to do second and third passes without nosediving into the material it would work fine. I'm usinf autodesk artcam 2017, and saving to axyz and .nc format. Any ideas would be helpful.
    Thanks

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  2. #2
    Registered Jim Dawson's Avatar
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    Default Re: Z height on second pass - help needed

    I'm going to guess that your machine is expecting incremental moves, and the G-code is output in absolute moves. Can you post the G-code for a simple part?



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    Default Re: Z height on second pass - help needed

    If you study the code, the cause would be obvious. Postprocessor may not be outputting codes suitable for your machine settings.



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    Default Re: Z height on second pass - help needed

    Hi Jim,

    this is partial code for the number one, outside vector cut. Hopefully this is enough.

    Thank you in advance,
    Dan

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  5. #5
    Registered Jim Dawson's Avatar
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    Default Re: Z height on second pass - help needed

    N90 G1 Z0.000 F254.0 First pass depth,

    N5400 G1 Z-2.540 F254.0 Second pass depth

    Is the machine not doing this? Should be 2.54mm (0.100 inch) deep.



  6. #6
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    Default Re: Z height on second pass - help needed

    Upon closer measurement, yes it is. Now I'm thinking that's too much for the machine to handle in aluminum. Is there a way to get the machine to do more, thinner passes. The first pass it just lays out the vector perfectly. Then second seems to bite off more than it can chew.. I'm ok with like four or five passes. I found that the third and final pass would be 4.82mm which is desired depth.

    Thanks
    Dan



  7. #7
    Registered Jim Dawson's Avatar
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    Default Re: Z height on second pass - help needed

    In the Artcam software, there is a way to set the Depth of Cut. I'm not familiar with that software, but I know that parameter is there. it's in all CAM programs. Not sure what it's called in Artcam.



  8. #8
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    Default

    Quote Originally Posted by Jim Dawson View Post
    In the Artcam software, there is a way to set the Depth of Cut. I'm not familiar with that software, but I know that parameter is there. it's in all CAM programs. Not sure what it's called in Artcam.
    Hi Jim,
    Just wanted to thank you for the help. I've got it running now. Basically what I have done is tricked the machine and software by putting a lower material thickness and relief final thickness. The machine doesn't bind or jam anymore. After each toolpath is run, I reset the Z height and I just do more passes. It's tedious and prevents me from creating templates to save time but for now it's fine until I can purchase a larger machine one day. Thanks again for the insight.



  9. #9
    Community Moderator ger21's Avatar
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    Default Re: Z height on second pass - help needed

    The problem is that you don't know how to use ArtCAM. Find some tutorials, and learn how to use it, rather than learning how to do workarounds.

    Gerry

    UCCNC 2017 Screenset
    http://www.thecncwoodworker.com/2017.html

    Mach3 2010 Screenset
    http://www.thecncwoodworker.com/2010.html

    JointCAM - CNC Dovetails & Box Joints
    http://www.g-forcecnc.com/jointcam.html

    (Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)


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Z height on second pass - help needed
Z height on second pass - help needed