Question regarding Corel Draw x5

[MrKriez]

I have a question that hopefully someone can help me out with. When I make a circle in Corel Draw x5 and save it as a .dxf i notice that the circle is not a circle anymore but a bunch of short straight lines trying to make a circle? Is there something that I am doing wrong when I save the file as a .dxf?

[beefy]

Try a different version of the dxf export. I normally use 12 or 14 and seems to be OK. By the way there's a Coreldraw specific section in this forum.

Something I've recommended several times is DXFTool for Coreldraw http://www.CorelDRAWTools.com

I actually bought Coreldraw because of this plugin. The plugin is about $60 but I was also willing to pay for Coreldraw because of the dxf output functionality this combo gives. Coreldraws dxf output can be a bit crappy, lots and lots of nodes, etc. The DXFtool gives a huge reduction in nodes and gives smooth curves instead of lots of lines, etc. Then there's the reduction in file size. Check out the website where it shows an example of dxf export with and without the DXFtool.

Something also which is good about this plugin is the licensing method. Based on what James Leonard (the author) said on a thread on the Coreldraw forum, it seems the software is locked to one computer but if you change computers, James allows you to swap the license to the new one. If that's the case you effectively own the software forever. This contrasts with some Coreldraw plugins where you get 3 licenses tied to the coding on your hard drive so even if the hard drive is formatted you lose one of the licenses.

I started a thread on this matter and it got a bit heated so you may find it entertaining. Toward the end of it James talks about his licensing https://coreldraw.com/forums/t/38260.aspx

[Gamelord]

This is an issue with exporting the drawing out in DFX format. I have found that it is most universal for the majority of cutters out there to export the file with ver. 2.5 or 2.6. Problem is that it takes curves and segments them as you have noticed. You can export the DFX out using ver. 14, or ver. 2002 through 2008 and it will keep the circle a curve, but it doesn't always import into other cutting software properly and may actually mess up the drawing beyond repair.

One fix I have done for this is to take the circle, convert it to curves and then add in massive amounts of nodes to the circle so that when it breaks it into segments, they are so small that it still cuts relatively smooth and is not noticeable.

[MrKriez]

I will look into that CorelDRAW Tools pack you listed. The biggest problem I have with the circles being lines is I do all of my cutting on a laser. Once I've converted the dxf into a part and nested it I sometimes get errors when trying to cut it. It's a simple error on the laser in that I just have to add [G40x0y0] into the line with the error and problem is gone. The problem I run into is at the laser I can only see up to the first 6000 lines in the editor. So anything to cut down on the lines is a good thing, since a normal circle on the laser is only 2 lines of code but a Corel Draw x5 circle is a lot.

[Gamelord]

If you are getting individual line segments for your circle instead of a solid line that is not curved but segmented then that might be the program you are importing the DFX into that is causing it...or the version you are exporting the DFX out as.

If you import the DFX into Corel and it has thousands of individual segments making the arc, then you would want to use the "Join Curves" tool to connect all the segments into a solid object. Once done, then my above post can be used to make the curve more ... curved. With laser this may still be a problem due to the accuracy differences between Laser and Plasma.

If you join the curves to get rid of the individual segments, and then when you import the DFX into your laser and they're back, the issue is either the version you are exporting out as or with the import features of your Laser program. I am using X5 and exporting to DFX does not break the curves apart into segments....so I can only assume that it is your Laser program that is doing it.

[SignTorch Vector Art]

if I remember right, in later versions of corel, if you just export an ellipse to early dxf (without splines) it will get broken into like 16 or so line segments around the whole thing, which is not enough to appear smooth

I think, if you convert the ellipse to a curve first, then it will look the same but when exported it will break into more line segments and appear much smoother when exported to early dxf without splines, to make it even smoother you can just add some more nodes so it has more than 4 nodes to start with

if you use some arc curve fitting software like dxf tools, the arcs can be exported to dxf (any version) as true circular arcs, eliminating the need for splines or short line segments and different dxf versions altogether

technically, there is no such thing as a circle (or arc) in corel draw or in corel draw output, in corel everything is a bezier curve very similar to the nurbs and spline curves in later dxf versions, those are not standard gcode entities, so a certain amount of translation and or approximation and or degradation is always necessary to turn vectors into gcode. In the image above it is a mistake to call something with nodes a circle.

as for having to enter G40X0Y0, that's wierd, barring some other G4x command overriding it, you should not have to set G40 more than once, usually at the beginning of a program or during initialization, it seems untenable to have to fix code while cutting, so good luck on getting that fixed..... it is plausible that your cam software uses G40 to accomplish kerf compensation such that setting it to zero might not be ideal, I don't know, just guessing....

[Dawgonhawg]

Anyone else using the DXF TOOL software or do you have any pros/cons to add?

Your input will be appreciated, Jim

[MrKriez]

... as for having to enter G40X0Y0, that's wierd, barring some other G4x command overriding it, you should not have to set G40 more than once, usually at the beginning of a program or during initialization, it seems untenable to have to fix code while cutting, so good luck on getting that fixed..... it is plausible that your cam software uses G40 to accomplish kerf compensation such that setting it to zero might not be ideal, I don't know, just guessing....

I do know the software we use is fussy. For parts it is fine, but any artwork is where there are issues. I will usually have to run it at the laser in graphical mode to go through all of the code and look for any problems it may have. That and with the curves being drawn as lines, the software will sometimes not see that they are connected and leave me with an Open Contour. Even if it is just 0.001" it will still complain about it, and that will then mess up any leadins or leadouts it may do.