Meshcam DXF Problem

I’m having issues importing a DXF file into Meshcam. I am trying to mill some knife handles. I’ve decided to break it up into multiple projects so I can use different tools for different operations. I am using Onshape for the design.

One of my operations includes just milling holes. So I import my STL and the want to import a dxf of the holes to use as my regions to mill. It does import, but half of the holes are out of position. I opened the dxf in Visio and Edrawings and it looks correct. However Meshcam seems to have issues with this. I read that Onshape exports dxf as R11 and didn’t know if that has anything to do with it. The image being offset may have something to do with the way Onshape exports relative to the origin. Notice though on the bottom half how the holes are out to the left. If you look at the dxf file the are a mirror image of the top.WR_Skinner - Holes.dxf (9.3 KB)

Is this a bug? Any help here would be appreciated.

Also, it sure would be nice to be able to reposition dxf files in mescham.

@PDG, you do need to have your DXF origin in the same place as the geometry origin. I imported your DXF into my 2D CAD program (VersaCAD) and the origin is in a seemingly random place.

But all the holes are in the correct position. They are all on the same layer. But the right-most holes are not circles–they are two arcs apiece. Try replacing them with circles and see if that helps. With the outer rectangular border, the resulting nested outlines might not work the way you intend either. You might need to delete the border.

About the holes, since they are on contoured surface I’d just roughly hand-draw machine regions around each and use the typical waterline+pencil finishing, with a waterline angle limit of, say, 45 degrees. That should cleanly machine the holes.


@Randy, changing the arcs to circles fixed the import issue (not sure why but good catch). You are correct in that the origins are in seemingly random positions. Unfortunately Onshape will not let you define your origin. As my entire drawing developed (starting with the knife blade), the handles ended up and some point away from the origin. I’m hoping they will add the ability to do this. I suppose the only way to take care of this is to perhaps copy the handles only to a new file and move them relative to the origin to try and make this line up better.

@PDG, I don’t use DXF myself for machining regions. I experimented with it early on but basically found the same thing you have–the STL and DXF need to be rigorously aligned before importing to MeshCAM.

But I have not needed the DXF machine regions. As I mentioned above, you can use various controls/filters in MeshCAM itself to tailor where you are machining. Filtering by slope of the surface is a pretty powerful control, becuase the hole walls are vertical and the surrounding surfaces are gently sloped. Give it a try and I think you’ll find it is less bother than dealing with the DXF. :smile:


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@Randy, Thanks for the help. I’ve been experimenting in MeshCam to see what I can come up with. Looks like you can get creative with things and come up with some interesting results.