MeshCAM cutting out shapes.


Results 1 to 8 of 8

Thread: MeshCAM cutting out shapes.

  1. #1
    Registered
    Join Date
    Nov 2010
    Location
    United States
    Posts
    9
    Downloads
    0
    Uploads
    0

    Default MeshCAM cutting out shapes.

    I am trying to cut out some prismatic parts and MeshCAM does it ok BUT there is an issue I just can not get it to stop doing. When I set global parameters to machine geometry + 6.3 (mm) it goes around the object in two paths; I just want it to go around my object once (see pictures) and cut out the shape at the width of the bit but it insists on doing 2 passes or else the tool path will not fully generate. I tried to be smart and set the machine geometry to + 3.15 (half the thickness of my bit) but it does not fully generate the tool path. This is hard to explain so I attached photos for reference. You can see the 2 paths around the shape and then in the other photo a not fully generated tool path.

    I only have 3 days left to evaluate the program and if I can't get it to stop doing this then I don't know if I will want to buy it. I also noticed some other silly issues such as excessive rapid moves and everything being in MM except the step-over being in inches.

    Similar Threads:
    Attached Thumbnails Attached Thumbnails MeshCAM cutting out shapes.-mesh2-jpg   MeshCAM cutting out shapes.-mesh1-jpg  


  2. #2
    Registered
    Join Date
    Apr 2003
    Location
    Southern California
    Posts
    178
    Downloads
    0
    Uploads
    0

    Default

    It looks like you're using roughing to cut that out- you should use a combination of waterline and pencil for the cutout toolpath.

    For a better look at the MeshCAM 2d workflow, check out Using MeshCAM to Cut 2D Objects

    -Rob

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


  3. #3
    Registered
    Join Date
    Nov 2010
    Location
    United States
    Posts
    9
    Downloads
    0
    Uploads
    0

    Default

    The main reason I wanted to use roughing is because it does everything I need in one step and it can cut my object out in about an hour. I am just really kind of curious as to why the roughing operation takes 2 passes on the outside of the part. (I am not trained in CNC or machining) If I could "disable" this and get it to do one pass I could half that work time with as far as I know no issues.

    I do like the program, I like it a lot but my evaluation is about to end and I don't know if it is capable of doing everything I need and don't think I have the time to find out. I'll probably buy the program though; it is by far the best simple program out there...I just wish there were a few more options here and there for people between not knowing anything and people knowing enough to be dangerous!



  4. #4
    Member ger21's Avatar
    Join Date
    Mar 2003
    Location
    Shelby Township
    Posts
    35538
    Downloads
    1
    Uploads
    0

    Default

    The main reason I wanted to use roughing is because it does everything I need in one step and it can cut my object out in about an hour.
    Is that part just flat cut out of sheet material? If so, you should be able to cut it out in much less than an hour.

    MeshCAM is really a 3D mesh machining program, and your part is a simple 2D part. Look at the link Robert sent you for 2D machining in MeshCAM. It might take a few minutes more to set up, but it should machine much faster.

    As MeshCAM is mainly a 3D program, the roughing passes are mainly intended to remove the bulk of material from a block, and probably aren't optimized for parts like yours, where a roughing pass is not normally needed.

    And if you email Robert and ask him, there's a good chance that he'll extend your trial period.

    Gerry

    UCCNC 2017 Screenset
    [URL]http://www.thecncwoodworker.com/2017.html[/URL]

    Mach3 2010 Screenset
    [URL]http://www.thecncwoodworker.com/2010.html[/URL]

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

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


  5. #5
    Registered
    Join Date
    Apr 2003
    Location
    Southern California
    Posts
    178
    Downloads
    0
    Uploads
    0

    Default

    Extending the trial is no problem- just email me when it shuts down.

    For your part, the roughing does not appear to be necessary. The waterline passes will follow the exact contour of the part and let you stepdown a reasonable amount to keep from overloading your cutter/machine. The pencil pass will do a final full-depth cut for anything remaining.

    The terminology used above mat be a little different than a traditional 2D CAM program but I suspect that the finished toolpath will be reasonably efficient and require very little effort on your part.

    As for why the roughing takes two passes, it's trying to remove a volume of material defined by the part boundary and the area to be machined. It will try to remove all material between the two of them. You are only looking for the part boundary to be cut so roughing is the wrong strategy for this particular application.

    -Robert

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


  6. #6
    Registered
    Join Date
    Nov 2010
    Location
    United States
    Posts
    9
    Downloads
    0
    Uploads
    0

    Default

    Thanks for taking the time to help me with this guys! The part is plastic actually and it has recesses that need to be cut out as well. I tried waterline and pencil cleanup before and wasted a good piece of stock when it did not fully cut out the 3 internal slots though it did only go around the stock one time rather than 2 times. You can see down by my gizmo the job that the two operations (waterline and pencil) do on my semi enclosed cutout. If I do roughing though it will do a fantastic job on cutting out the part (regardless of if it is proper or not) and that is why I have used it. So I must be missing something. I have had to work 12 hour days the last couple days and haven't had a chance to do anything except post.

    Attached Thumbnails Attached Thumbnails MeshCAM cutting out shapes.-mesh3-jpg  


  7. #7
    Registered
    Join Date
    Apr 2003
    Location
    Southern California
    Posts
    178
    Downloads
    0
    Uploads
    0

    Default

    Not sure what material you're using but if you can cut the pockets to full depth in one pass then just enable the Parallel Finishing, set the threshold angle to 45, and check "Don't Machine Top of Stock". That will machine anything flat below the top of your model.

    If you need a roughing pass with to cut the pockets in multiple passes then I'd probably create a second toolpath using the Set Machine Region command to select only the pocket areas and do everything above but also turn on the roughing. That will give you a complete roughing/finishing toolpath only for the pocket areas.

    Robert

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


  8. #8
    Registered
    Join Date
    Nov 2010
    Location
    United States
    Posts
    9
    Downloads
    0
    Uploads
    0

    Default

    I am doing HDPE but my machine is wooden so no chance on doing one pass cutouts. I never thought about doing it the way you describe and it looks like that is the ticket! It never crossed my mind to have 2 jobs to cut out one object but that is going to lower my machining time down to about 30 minutes per part! I will email you as my trial expires. Thanks so much; I was not expecting help from the guy who made the program.



Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


About CNCzone.com

    We are the largest and most active discussion forum for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

MeshCAM cutting out shapes.

MeshCAM cutting out shapes.