Tip for modifying boxes.py objects

I used the website boxes.py to design a simple box for an Arduino project. I exported the design to LightBurn. I wanted to “drill holes” in one of the box sides for electrical and sensor feeds, so I drew a circle object in LB and tried to do a boolean subtract from a side object from boxes.py. Nothing happened. Apparently the side object was not recognized as a closed shape. But I discovered an easy workaround: I select the side, then Tools>>Offset Shapes, then set the offset to 0 mm and selected “Delete Original”, and LB created an identical-looking object that accepted a boolean subtract of the circle. Just thought I’d pass that along…

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I might be misunderstanding your goal but I think you’re over-complicating things. There’s no need to perform any boolean operations to get your hole, just make sure your circle is on a cut layer (most likely the same layer as your main outline).

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You’re thinking Auto Cad type stuff…

Lightburn simplifies most of this for lasers.

:smiley_cat:

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Yes, you are both right, I have been influenced by thinking like a CAD operator. I do use FreeCad to design for my 3d printer. FreeCad maintains an indentured list of shapes that are subjected to various boolean operations to yield the final shape to be printed. What’s nice about that is that you can go back to any layer of the list, change a shape parameter, and the change flows through the logic to the final shape automatically. Basically, all the primary shapes, and the logic used to reach the final shape, are maintained. With LightBurn (which I love!) I can use Cntl-Z to go back to an earlier state if I need to make a change, but the logic forward is lost, as far as I can tell. So you must redo the logic steps manually.

What you want is something that can be parameterized so you can change value A and it will propagate throughout the entire project… hopefully…

I use freecad for some things that I know I’ll probably need/want to modify that will be more difficult in Lightburn.

I have a flow meter housing for the co2 that I drew up in Freecad. 3D printed the case, and laser cut the lid…


Lightburn is a great piece of software, but it targets lasers, Gimp, Illustrator target graphic arts… both can overlap, but nothings better than the right tool for the right job.

:smiley_cat:

Yes, it’s easy to get stuck in a particular way of thinking. I’ve been using CAD since the late '80’s (AutoCAD 2.6 on DOS back then, but obviously non-parametric), SolidWorks since about 2001 and Fusion 360 since 2017. I’ve got to admit that I really miss the advantages of a parametric system when I’m using non-parametric software such as LightBurn or CorelDRAW.

I think that’s something you really can’t retrofit to existing software… That kind of stuff has to be designed in it from the git-go…

:smiley_cat:

Yes, unfortunately I think you’re right. As a consequence I don’t see it coming to LB any time soon - if ever :sob:

I subscribed to https://cuttle.xyz

2D parametrics and copy and paste to LB. Pretty easy to create parametric files. Worth the cost if it fits your needs. You can create a few files in the free version.

As much as this is the case I suspect the reverse scenario would likely have more things to miss. Even the idea of moving or rearranging multiple shapes on the workspace sounds like a chore in a parametric solution.

I think there are some concepts from parametric modeling that could be brought in without a complete architectural change. Things like specified distances between shapes, size relationships between shapes, constrained angles, etc. Those would only require attributes between two shapes or all within the shape.

However, I personally would be heavily opposed to a fully parametric workflow as I don’t think the tradeoffs are worth it for where LightBurn excels. I can’t even imagine the number of complaints about how “hard” simple things should be.

The existence of something in the software doesn’t mean you have to use it or even know about it. I agree I’d hate to have that forced into my work flow.

Look at all the goodies in Lightburn that most people don’t use or know about… I seem to find new ones quite frequently…


I know of no one tool that works well for any and all applications. I use Gimp to dodge and/or burn a photograph and when I need parametric design it’s available in another package… 90% of the time most of what I want to do, laser wise, is handled fine with Lightburn… probably more than most packages.

:smiley_cat:

Depending on how it’s implemented. Normally parametric solutions are all or nothing. If you’re designing, you’re parametric and need to respect the parameter history.

I suppose LightBurn could offer a separate parametric mode that allows you to design a shape parametrically and have it come back into the normal workspace. That would be basically an entirely separate application, however.

I read you here… that’s why I stated it probably has to be designed in…


I’m looking at it from a different perspective … With Freecad, it’s there designed into the system, I can use it or not. No real effect on the user.

You’re viewing it from a software side of carrying all this information around with each object that is there or could be there, would be a daunting task.

:smiley_cat:

I remember my first encounter with FreeCad, and it was daunting to the max (until I found the “Parts” workbench). I coined a maxim for good software many years ago, when I released my first software package that others were going to use. I said: “The program is designed so that easy tasks are easy to do, but complex tasks are possible by drilling down into options.” (April 22, 1976).

While LightBurn may not have full parametrics, it is still a joy to use, and extremely useful for its intended purpose. Love the “mail merge” integrated into the array tools. Edit Nodes is the best implementation I’ve seen for changing Bezier curves and shapes. I use rubber band and Offset Shapes all the time. A little daunting to see “Settings”, “Machine Settings” and “Device Settings” on your first day, but you quickly get the hang of things.

I was hoping to see a “Cntl y” to complement the Cntl z, but I’m usually not going back very far to correct things.

Assume you know you can edit some of them…

:smiley_cat:

Oh, what I meant by the “Cntl y” comment was that some software allows you to do multiple Cntl z’s to undo sequential operations, and then use Cntl y to redo them automatically, skipping steps optionally. That way you can go back, change something, skip that change step, and continue back up the drill-down. kludgy, but effective.

I see from your reference that Cntl-Shift z is the LB undo, and I did not realize that, so thanks!

Ctrl-Shift-Z is redo. I believe this can also be remapped with the new-ish shortcut editor.

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