I have a 900x600 laser, and a file with about 230 individual parts that will need many different sheets to complete.
When I import my dxf file, I have a heck of a job going through and organising which parts fit and selecting/deselecting which to cut.
So, I have to do all of that outside of Lightburn and then bring the nested file in to cut.
One thing I like about Lightburn is that I rarely have to go out to a third-party app to get things done, so a built-in nesting tool would be a real boon.
Thereās a few open-source ones to look at that could become the basis for a Lightburn nesting tool:
The problem with open source is that if you use them in your software, you have to make your software open source as well. OZ will need to write his own nesting software if he wants to add the feature to LightBurn.
That is not always true, it depends on the license. I checked deepnest and itās license allows for commercial use in closed source projects. That said, many devs donāt want to deal with the legal aspects of using open source and will just roll their own to avoid it.
I emailed Oz a while back to see if he had considered investigating the possibility of incorporating Deepnest code into LB. He said he had looked into the coding/design and that it wasnāt a good candidate for being part of LB.
SVGNest has a permissive license, though Iām not sure if DeepNest does as well. Both are primarily written in JavaScript, and not nearly as modular as they could be. Implementing nesting is on my wishlist, but itāll take a chunk of time to do.
After doing some more work with Deepnest, Iāve come to the realisation itās a complete pile of poo. It does a great job of nesting, but it doesnāt handle dxf files properly - my 380mm object came in at 1077mm.
After playing around some, I managed to get it in at 400mm-ish. Not close enough.
What kind of numb nut produces something that changes the scale so badly?
Apparently the author hasnāt been seen since he produced it - thereās an increasing bug list and he hasnāt addressed a single one, so Deepnest is off the list.
Iāll give SVGnest a look, but never work in SVG files and would have to do multiple conversionsā¦ grrrr.
DXF files do not store the unit of measure used, so that could be the issue. If you saved it in cm but load it as inches, for example, the scale would be 2.54x larger. Iām amazed that DXFs (being a CAD / engineering format) have this issue.
Iāve dug through the code a bunch and itās a bit of a mess, and almost entirely written in JavaScript, so it would need a full port. Itāll happen, but itāll take time.
Yeah, Iām not new at thisā¦ 40+ years of systems engineering means I donāt make basic mistakes like mix up mm and inches. His app is flawed.
I never use inches, for anything. It would take a conscious and determined effort. Iām a product of binary, decimal/metric and hex. You can keep yer weird base-12 Latin nonsense. Heck, Iām for going full metric calendar!
Iāve tried putting in various numbers to the SVG ratio to try and work out where the calculation is. I suspect heās converting from metric to inches and back multiple times and building up such a set of rounding errors that my 6mm becomes 6.92mm in just a few moves. Iāve seen that kind of thing in CNC apps and slicers, too.
And thanks for the commitment - nesting is such a time-consuming task and if you can knock it off, will truly make this (more of ) a standout product.
Andā¦ while weāre on the subject of shape management, I would like to see some method of chaining jobs.
For example: I have 7x sheets worth of shapes to cut. How I handle it at the moment is to manually nest a full sheet, group it and assign it to a non-cutting colour. Repeat for the other six sheets. Then I pick a sheet, assign it to a material, flip the ācutā tag, move it to the centre and run. Repeat for the other six.
A way of stacking those seven groups and running through them sequentially would be fab.
Of course, I may just be looking at it wrong (itās been known to happen) and my workflow is whack.
I had a similar problem with things not scaling correctly. I try to convert to .svg first since it seems to work best. It is funny how you can run the same file multiple times and get different results each time. Sometimes barely different in terms of efficiency but other times unacceptably different. Nature of the beast I guess but you have to hope you donāt get a bad ārunā if you only run it once.
You know the same guy wrote svgnest and then Deepnest, right? Each has its flaws but at least svgnest is free. Since he isnāt making money on it, I give him props for maintaining a website that can sometimes be helpful.
No, the developer of deepnest took svgnest and added stuff, like dxf import.
Svgnest works fine, but I was trying to avoid another conversion.
And if he maintained it, it would probably be fixed. He has 58 outstanding issues, some of which date back to when he released the app. Heās not replied to a single one.
Heck, Iām for going full metric calendar!