Struggling to get the outline

[blrose88]

I am new to plasma cutting and I am trying to cut out this cross. I only have inkscape as of right now. I have been trying to just get the outline without the leaves. Any help would be very appreciated!


Thanks, Nick

[acourtjester]

Here is what I did on Inkscape, import the image and click on "trace bitmap" then select "brightness cutoff". Run the threshold up to about 940 and click update. Slide the black image over and remove the original. The do fill/stroke and remove the fill and click on stroke and give it a color. Next do break apart under the path menu (sometime also ungroup under object menu). This will set it up to select and remove sections of the drawing. have the image selected and go to path and do "simplify" this remove many of the nodes. YOu can use the node tool and remove unwanted nodes and refine the shape to your liking. the second image shows that you have broken the image into parts for the removal of nodes to start.

a cross 6.JPG (41.4 KiB) Viewed 1178 times

a cross 6.JPG (41.4 KiB) Viewed 1178 times

a cross 3.JPG (32.65 KiB) Viewed 1178 times

a cross 3.JPG (32.65 KiB) Viewed 1178 times

[acourtjester]

Go to this post and watch the attached video on Node removal and refining.
viewtopic.php?f=77&t=33230

[blrose88]

Thank you so much for the help!

[adbuch]

Tom - my Inkscape auto trace didn't come out as clean as yours did. But this would be a good one to practice on for node editing. Delete all unwanted nodes, and then move some around to smooth out the outer perimeter. Great job and a nice explanation.
David

[acourtjester]

One thing you may not have done is going high enough with the "brightness Cutoff" I went to about 940-950 which is almost all black with no outside noise showing. Then remove the fill, that should show less of the internal nodes. The break apart and selection the outside edge to only have the border which is what the OP was looking for. The second image show some of the internal sections that can be removed by clicking on them then delete.

[blrose88]

I am trying to see what I did wrong with the file in inkscape. When I change the size it doesn't stay the same, the lines blend together and distort the image. Any help would be greatly appreciated.

Thanks, Nick

[adbuch]

I opened your dxf and it looks fine. What size to you want it?
David

cross 5 image.jpg (50.07 KiB) Viewed 1100 times

cross 5 image.jpg (50.07 KiB) Viewed 1100 times

[blrose88]

I was trying to make it 12 inches tall.

[adbuch]

cross 5 at 12 inches tall.dxf

(24.17 KiB) Downloaded 48 times

cross 5 at 12 inches tall.dxf

(24.17 KiB) Downloaded 48 times

[blrose88]

Thank you. If you don't mind me asking, what software do you use?

[adbuch]

Thank you. If you don't mind me asking, what software do you use?

I use a combination of Paint.net, Inkscape, and Design Edge.
Paint.net to prepare bitmamp image for auto tracing
Inkscape for auto trace (trace bitmap)
Design Edge for editing dxf to create cut ready file

David

[adbuch]

One thing you may not have done is going high enough with the "brightness Cutoff" I went to about 940-950 which is almost all black with no outside noise showing. Then remove the fill, that should show less of the internal nodes. The break apart and selection the outside edge to only have the border which is what the OP was looking for. The second image show some of the internal sections that can be removed by clicking on them then delete.

Tom - thanks for that! I know you use an older version that actually shows the changes when you hit the update button. Mine doesn't do that, so I would need to close out the trace bitmap window to see what it looks like, and then reopen to make adjustments. Thanks for your quick tutorial on editing out the unwanted nodes. Very helpful to many here.
David