topic include ellipse in polyline join in AutoCAD Forum

include ellipse in polyline join

MikeKovacik4928 — Wed, 01 Sep 2021 07:26:15 GMT

Hi all.

I very rarely use autocad anymore, after having used it for more than 30 years.

We use Inventor now for everything new, old drawings were 2d autocad.

Redoing all old 2d autocad drgs as 3d inventor models, assys, and idws

However with autocad, how do you include a half ellipse into a polyline. When I do the pedit command, join,

and select all it doesn't include the semi ellipse. The semi ellipse is touching, there appear to be no gaps

Mike Kovacik

South Africa

Re: include ellipse in polyline join

tramber — Wed, 01 Sep 2021 08:33:15 GMT

No way to integrate an ellipse or a piece of spline. You need to turn it to a polyline.

My trick is not tu use PEDIT anymore but the command JOIN (that appeared while you were playing with anotehr soft !)

JOIN, select all. It should turn the all into a spline, then you need to convert it if needed, back to a poly.

Re: include ellipse in polyline join

MikeKovacik4928 — Wed, 01 Sep 2021 08:40:54 GMT

Thanks

That works. It is now all one spline. If I want to convert that spline into a polyline, how do I do that?

I am using this to convert into a dxf to put into sheet cam a profile cutting program.

Even as single lines, the profile cutting worked okay (all the end points were joined there were no gaps)

I guess the spline will be okay for the sheet cam software.

I supposed it doesn't matter what the dxf is , single entities joined without any gaps, a single polyline,

or a single spline?

If somebody with profile cutting experience on sheetcam is out there, their comments would also be appreciated.

Mike

Re: include ellipse in polyline join

tramber — Wed, 01 Sep 2021 09:42:05 GMT

Let's not go too fast !

That really depends on the softwares that are installed at the end of the process.

In the ancient times, my grand-father 😁 use to export under DXF 12 and it converted automatically into polylines....

Nowadays, it depends...

Take your phone and check with the owner of the machine. Why wouldn't you try to send as is.... ?

_SPLINEDIT has an option to convert, in case.

Re: include ellipse in polyline join

tramber — Wed, 01 Sep 2021 09:45:48 GMT

By the way,

PLINECONVERTMODE to 1 before the operation will give you arcs. Better ?

Re: include ellipse in polyline join

MikeKovacik4928 — Wed, 01 Sep 2021 10:48:31 GMT

I am doing the sheetcam programming for our own plasma cutting machine.

It was just natural autocad based curiosity on my part as to combining the ellipse into a polyline.

I am happy to have learned about the join command converting all into a spline.

As to how the plasma cutting machine sees it, that had nothing to do with this forum, I was just

chancing it that some other autocad operator was using sheetcam

As far as I can see it doesn't matter whether the dxf file is derived from

1. entities joined together

2. single polyline

3. single spline

the g code generated by Sheetcam exports co-ordinates anyway of all relevant co-ordinates needed for cutting

Mike

Re: include ellipse in polyline join

jrreid — Wed, 01 Sep 2021 16:32:59 GMT

This is one way of changing all of your Ellipse to Lines.

Open your drawing then type DXFOUT and select the oldest version you can. I used R12.

Close your drawing and open up the DXF file (you have to change your file type to see it).

Once in you have to explode all of your Ellipses. They are now line segments.

Then use PEDIT, select Multiple and select your entire drawing (or the areas you need).

Now when your options come up chose JOIN.

Now you should have all PLINES joined together. If they are not, then there was a small gap.

Hope this helps.

JRR.

Re: include ellipse in polyline join

john.uhden — Thu, 02 Sep 2021 16:45:34 GMT

@MikeKovacik4928

If you are drawing the ellipse in AutoCAD, try first setting PELLIPSE to 1. That way, when you draw an ellipse, AutoCAD will actually create a polyline that is very close to being a true ellipse. Then you can trim and join all you want.

Re: include ellipse in polyline join

tramber — Fri, 03 Sep 2021 07:37:37 GMT

This thread is quite full of aspects and solutions ! @john.uhden had a good idea to remind this variable.

Even if i guess that @MikeKovacik4928 obtained ellipses but didn't creat them.... !?

Re: include ellipse in polyline join

leeminardi — Fri, 03 Sep 2021 12:22:39 GMT

I created the following Screencast yesterday about creating a spline that is tangent to a line. It was in response to a different post. I think it might be relevant to this post where you have an ellipse segment that is tangent to a line.

https://autode.sk/3hcekEf