Why can't I do a Boolean Union to Join the snowflake ornament with the text?

I was able to use the Union tool yesterday, without issue, on another project. Why can’t I Union to text to the rest of the ornament? I grouped the ornament, without text, selected both, and that didn’t work. I also tried close path and that didn’t work. Please tell me what I am doing wrong. Thank you in advance. I’ve attached the project which will be cut from 1/8 inch birch plywood. Mack.Christmas Snowflake Ornaments.lbrn2 (139.1 KB)

Lines are not connected in the lower right. See highlighted area. It will be different location for you. This image is mirrored for me.

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This is starting to feel like deja vu. @Dueller6 We had some excitement over this yesterday on a different thread.

There are a couple of conditions that must be met for boolean operations to be available:

  1. every path in the operation must be closed - meaning it must be an enclosed shape; not just visually but in the system
  2. can only work on 2 objects at a time - you can use grouping in order to treat multiple objects as one

If you’re having trouble with this it’s likely that for some reason the object’s path is not closed. Make sure you systematically close each path. I’ve noticed that trying to close the path of a grouped object as a whole is not the same as ungrouping everything, selecting everything, and closing the path. So make sure you’re closing every individual portion of the pre-grouped item, closing the path, then regrouping as necessary.

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Thank you. I’ll try these suggestions. I REALLY appreciate the fast response! Merry Christmas.

If you need help fixing it let us know.

Ralph, yes, that worked. I’m somewhat new to LightBurn but use VCarve Aspire on my CNC mill so I’m familiar with most CNC operations. If it’s not too much trouble will you please point me to a resource or tell me how you detected and closed the paths. I tried “close paths” from the menu before my first post but perhaps it’s because the ornament itself was group. Thanks again!

Just for reference, I did not have to manually adjust any nodes to connect them when I tested this. I was able to use Edit->Close path alone to get this to work for all 4 ornaments. With my experience from yesterday I’m beginning to question my understanding of how this works or wonder if there’s some wonkiness at play.

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There is some wonkiness going on. I had to ungroup the ornament to boolean the name on your file @berainlb

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Can confirm there’s some wonkiness on trying to automatically close paths and shapes etc.

Was driving me bonkers this morning trying to design ornaments!

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Would be nice if we could identify a simple scenario that reproduced the oddity but I’ve never been able to do this predictably. I did see in searches that paths and joining have been discussed at length and there are some known problem cases.

I usually only see this in imported objects and I think mostly with DXF. I think grouping can also come into play. I don’t think I’ve seen this in objects created within LightBurn although I don’t use LightBurn to create anything complex directly.

@LightBurn mentions a long-term plan to rewrite some of this to potentially avoid some of these scenarios that make joining hard.

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My comment wasn’t an indictment on DXF as a format or LighBurn’s proficiency in reading it. More an observation on times I’ve seen issues. Whether that’s because the format itself is tolerant to poor implementations, hard to generate correctly, or just suffers from ubiquity as an interchange format where bad files exist I don’t know. I don’t think I’ve ever had an SVG file exhibit the same behavior although I’ve had some files not load at all.

The release notes for a v0.6.07 highlight some of the challenges:
LightBurn v0.6.07 - DXF join fixed for good, Linux version, position r – LightBurn Software

But good to know that when done correctly that it can work reliably and with quality.

I had never clicked on your profile before. Nice website! I am making some Bernie ornaments thanks to you! I made some Trump already.

Oh I see, yeah lots of open ends. I spent an hour trying t fix some designs this morning, maybe longer.

Thank you all very much for helping me solve my Union issue. I did test with an Adobe Illustrator version of the file and it worked fine.

Let me summarize what I think you guys taught me. Make sure you don’t have open shapes. Ungroup the object, Select Open Shapes, Go to Node Editing Mode, Close each open shape. Regroup and then perform the union. Sometimes you can use Edit–>close paths. Or sometimes you can ungroup and regroup the object and it may work. Thank you again to everyone and Merry Christmas!

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You are getting it. Any other problems just ask. You’ll get into your own groove solving these problems. As you can see there were several different ways to accomplish this task.

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I think some DXF export routines, export each line segment as a single open entity. So you would need to join them as Polylines before closing them.

I don’t know how to join line segments into Polylines in Lightburn myself… haven’t used it enough recently due to work commitments.

You can join adjacent but unconnected line segments using “Auto-join selected shapes” in the Edit menu.

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