CNC Export Vector Breakup

bart_harris

I exported a few sketches to .DWG and .DXF for CNC routing.

When I imported them into PartWorks it had broken each sketch into separate vectors, which meant that I had to manually fix them in CorelDraw.

Does anyone know why this might have happened and how to make them one continuous vector? Here is an example of one of the sketches. This one was broken up into eight vectors: four edges and four curved corners.

https://cad.onshape.com/documents/89d21b4e63624f45b1d3fc3e/w/10e564195f6449daaef1bffe/e/97f9c4d1a896448998a96dfd

Many thanks.

andrew_troup

Vectors are inherently discrete, and it seems to me that what you are asking for could only be achieved by approximating a chain of geometrically primitive geometry (eg lines and arcs) by a single spline. There is currently no "fit spline" functionality in Onshape, so this substitution would have to be done in another package.
At least, that's how I see it.

3dcad

May I ask what cnc machines are you using for producing these?

bart_harris

I'm using a ShopBot.

andrew_troup

Vectors are inherently discrete, and it seems to me that what you are asking for could only be achieved by approximating a chain of geometrically primitive geometry (eg lines and arcs) by a single spline. There is currently no "fit spline" functionality in Onshape, so this substitution would have to be done in another package.
At least, that's how I see it.

brucebartlett

We use to have a CNC profile cutter that had to have all entity's closed polylines for programming. We would export from Solidworks, open in autocad or draftsight and do pedit, join all profiles into closed polyline then export as a .dxf. This was a pain, glad when they stopped using this programming software. Can't see Onshape exporting as closed polylines, if thats what you require. 

I very happy with the current .dxf export for faces and sketches, I am now going straight out of Onshape and into trumpf trutops to program for laser cutting. 

bart_harris

brucebartlett said:

We use to have a CNC profile cutter that had to have all entity's closed polylines for programming. We would export from Solidworks, open in autocad or draftsight and do pedit, join all profiles into closed polyline then export as a .dxf. This was a pain, glad when they stopped using this programming software. Can't see Onshape exporting as closed polylines, if thats what you require. 

I very happy with the current .dxf export for faces and sketches, I am now going straight out of Onshape and into trumpf trutops to program for laser cutting. 

I don't know much about this sort of thing but it seems that you are saying the same thing in both paragraphs. Why isn't the pain equal in the second paragraph? How can I stop the pain?

brucebartlett

What I am saying is some programming software requires closed polylines to imported for programming.  This is requires extra processing to create and is a pain.

Not sure if closed polylines is what you require. You would have to find out from Shopbot.