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Michael Simpson Virgina
07-23-2011, 2:35 AM
OK I have an object. Its a set of gear teeth, an import from Gearotica. The probelm is the teeth are not a closed object. They consist of 3 parts, which are made up of curves. I want to join the end nodes together. But it is probelmatic. Sometimes I can join the nodes and others I cant.

I have tried grabbing the little arrowhead thinggies so that they touch but I cant get the join nodes option to become active.

Michael Simpson Virgina
07-23-2011, 2:41 AM
Never mind. I figured it out. I first have to combine the shape by selecting them and right clociking and selecting combine. I can then use the sape tool and select both notes and join.

Richard Rumancik
07-23-2011, 10:04 AM
Sometimes there could be a very small gap between entities. This might be only a .00001" gap but it is still a gap. This can easily happen due to roundoff errors in the math.

If you want to close a path that should be closed (looks like it is closed) then one way is to select all the objects, click Arrange ->close path -> closest nodes with straight lines. It will then extend any lines that have small gaps to meet the closest node. Might save some tedious work in some cases.

Mike Mackenzie
07-23-2011, 1:24 PM
I use the smartfill it works great on most files like this all you do is click inside the path and it fills it solid and creates a closed path around it add the outline get rid of the base copy and your done.

Richard Rumancik
07-23-2011, 8:20 PM
Mike, I have not really used SmartFill so I tried what you said on a file with breaks in the perimeter and it did not work. After reading the Help it seems that SmartFill works if there are overlaps, but not if there are gaps. So if the algorithm that generated the gear tooth created some gaps then it can't be fixed using the SmartFill, from what I see. You need to close the path in some manner. My method will add some nodes and short segments, but assuming that it is almost closed to start with that probably won't cause an issue. I'm assumimg the gaps are less than <<.001" if they are roundoff errors. If the double-nodes matter, it is necessary to hunt for the gaps and fix them manually, or combine nodes that are very close together.

Michael Simpson Virgina
07-24-2011, 12:42 AM
@ richard
Not sure what version you ar running but close path does not show up on X5.

Mike Null
07-24-2011, 10:05 AM
Under the arrange menu try experimenting with "join curves". You can set your own tolerances and it works quite well.

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Mike Null
07-24-2011, 10:18 AM
You can also select the shape tool and the curve then use "close curve" which should appear on your toolbar.

Richard Rumancik
07-24-2011, 12:41 PM
@ richard
Not sure what version you ar running but close path does not show up on X5.

Arrange ->close path . . . . seems to be in CorelDraw up to X4. By Mike's response it looks like they changed it Arrange ->join curves and added more options (such as tolerance of the gap to be joined.) I don't have X5 but I assume Join Curves was the replacement command for Close Path.

Mike, not sure what I am doing wrong but I tried the select curve/ shape tool/ close curve option and it displayed the option to close the curve. But it would not fill the shape, until I physically joined all the double-nodes at the joints. (join two nodes command). Then it would fill. To me, being able to fill is the test of a properly closed path.

I was looking for a procedure (I assume Michael was as well) that did not require selecting each double-node and joining, but rather a command sequence that would close up a shape with that has gaps, with the least amount of clicking. Can you make that command sequence do this?

Mike Null
07-24-2011, 3:49 PM
Richard

I may not be following your question but in the "join curves" example you can fill that with one additional click. That example had 4 gaps which I selected by selecting the entire object.

In the example below, a DXF file which always seems to have open curves, I selected it, colorfilled even though it didn't show then ran the join curves tool. Presto, the fill showed and the curve was joined. One click would also fill after the curve had been joined.

In this example the smart fill tool also worked with just one click, apparently because the lines overlapped.

For my purposes the join curves tool works better as I usually need to close curves for cutting rather than filling. With the smart fill I could remove the fill but I think the join curves will permit more of a "global" activity.

Richard Rumancik
07-24-2011, 5:40 PM
I don't have a "join curves" command in X4. I think it must have started in X5. As I said, I assume it works similar to my suggestion of using Close Path in X4. So I don't have any issue with that. We are doing much the same thing; I can't test your method because I don't have X5.

What I was commenting on was your second suggestion:

You can also select the shape tool and the curve then use "close curve" which should appear on your toolbar.

In X4, I can't make that command close a curve that has gaps, making it "fillable". It accepts the "close curve" command, but nothing happens and the corners still have gaps. I don't see a change visually after the command.

Mike Null
07-24-2011, 9:15 PM
I found the same to be true but overlaps do connect and fill.

Michael Simpson Virgina
07-24-2011, 10:52 PM
I tried all the methods mentioned and the only one that works is the following

1. Select two of the objects and combine them
2. Select the new combinded object. Yo uwill see the join points as little squares. Zoom in to one of those points and select the shape tool. Select both nodes with a rectangle selector.
3. Hit the join nodes button.

On many of the gears the teeth are in five parts. And this can be a timely process, but it is the only one that works consistantly.

Im using the contour tool and it will not work unless all the nodes are joined properly.

Mike Null
07-24-2011, 11:43 PM
Michael

In this example, a dxf file, the inner and outer edges close but the diagonal lines in the corners remain unattached using the join curves tool.

Richard Rumancik
07-25-2011, 9:43 AM
Michael, I think the method you need to concentrate on is Arrange ->join curves. (see Mike's post) This is the X5 version of Arrange ->close path. You need to figure out why it is not working for you because it should. Form what I see on the Internet this command is improved over the X4 Close Path. Close Path is a bit buggy when gaps are larger but I don't try to use it for that situation.

I assume you need to select all the shapes to be joined, then Arrange ->join curves. (Can't test exact command sequence as I have X4. Check the Help Menu for sequence. I don't think they need to be combined first.) Since your shapes probably have small gaps, the tolerance could be set very small to avoid erratic behaviour of the command.

If there are overlaps, then this might cause some "loops" to form at the intersection. This is probably not good, although .002" loops might be effectively ignored if you tried to laser cut the shape. But I dislike leaving corruption like that in a file. You could probably get rid of it by using the SmartFill inside the resulting gear shape, as it would just save the enclosed space and ignore any "loops" outside the gear profile. (But SmartFill won't work as a primary command as it needs overlapping segments, not segments with gaps.)

Michael Simpson Virgina
07-25-2011, 4:21 PM
Guys
I have done the arrange, join curves.
This was my first choice.

It is unpredictable on complicated shapes, or does not work at all.
An involute gear has 3, 4, or 5 sets of teeth. Each set will have a several hundred nodes. The key is to combine the sets, one at a time, then to manualy selct the two nodes you want to join, then use the joine nodes. This is the most acurate and it closes the shape perfectly.