It is close I suppose.
As previously stated, seems a little clunky but I guess if it is too difficult to make this a toggle switch option, then it will have to do. :-/
Thanks for the input!
For anyone else wanting this feature please upvote the feature request below. If enough people ask for it, perhaps it will get some attention.
Given the arms race of higher wattage diode lasers right now I am guessing this will become more and more of an issue. I imagine someone will have a 100W version by this time next year 
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Are you attempting to cut thru 3/4" pine with a diode laser without charring?
When you use Lightburn a lot, it sort of becomes personal when people blame their problems on Lightburn.
We all get along much better when that stuff is spotted, itâs just ignored, much like you advised.
We come here to help people get their lasers working the way they wishâŚ
Too bad he didnât give more informationâŚ
Might see if this could be applied. Clueless if it will help in what you want to do⌠Iâm kind of out of options.
Yup. Well ⌠minimal charring at least. It gets thru just fine on the bits with no knots. On some parts it can get through at 400mm/min in one pass. Nice golden brown cut ⌠no char.
But if it hits a feisty bit with a knot and/or some resin, it takes a few passes to get through.
Thanks Jack. That actually might work quite well. I was never much of a programmer, but I could kill it with a batch file back in the DOS days
The title of the post was tongue in cheek obviously. I donât think lightburn is deliberately out to set fire to my house. However I think my issue will become a more common posting as these low cost diode laser seem to double in power every year or so.
Like Mooreâs Law for lasers. 
The problem isnât that the diode is getting more powerful, they donât seem to be, itâs rigging up an array of them.
Most of these seem to max out at about 5 or 6 watts. They just stack more emitters and beam combiners to get a higher power output level. This always has limits.
Until the come up with a more powerful base level dpssl, I think these increases are limited.
No matter how you slice it, these are pretty amazing. We will have to wait and seeâŚ
I run with remove overlapping lines in optimisation settings.
Even re-cutting cold previous cuts is a problem for me. The small amount of carbon in the original cut seems to get hot and start burning really easily.
My dual feed roller setup has many advantages. The laser only moves in one line on the Y axis, X axis pulls the wood.
There is nothing near the laser under the work. I have a 90 degree strip of aluminium about 100mm under the lower surface which reflects twice and absorbs most of the energy, excess energy goes back to the underside of the piece and has never made the slightest mark.
I am loath to cut thicker than 5mm. For me 6mm ply starts burning. Youâre really brave attempting 3/4".
I cut thicker pieces of wood with a bandsaw, drop saw or bench circular saw.
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Whats stopping you, if you dont like the multi pass feature, or creating sandwich layers, running the program with 1 pass cut layer, and then when it finishes⌠press start again?
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I donât think asking that the software not overheat a particular section of material is particularly out of line.
Obviously the title of this thread is meant to be tongue in cheek. I am sure whoever wrote the software is a perfectly lovely person.
FWIW, that does not come across at all.
Cutting 9 mm acrylic with my 60 W COâ laser requires two passes at 90% power running at 5 mm/s and 10 mm/s. Cuts fine, doesnât overheat anything.
Running that exact same job in 3/4 inch plywood will, in actual point of fact, start a fire.
How can LightBurn recognize the difference?
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Participants can help better with a good description of the problem. You always have the option of emailing support@lightburnsoftware.com.
Let me summarize what Iâve picked up from the thread:
- You have a 48w diode laser
- You want to cut 3/4 pine in an intricate pattern
- You are new to both lasers and LightBurn
Hopefully, I have the above correct. Operating a laser safely is the responsibility of the operator - that means understanding:
- What your type of laser can do best (CO2, diode and galvo fiber lasers are all suited to different tasks);
- What materials are safe to cut/engrave (attempting to cut/engrave materials like PVC will result in chlorine gas which can kill you - and damage your laser);
- what is the right combination of speed/power to use for each material for cut/engrave
- Appropriate materials - you want the material to be consistent so that the same speed/power can be used everywhere⌠with plain wood the knots are harder to cut through; with layered material like plywood voids in the material and the type of glue used impact hte ability to cut - and some of the glues used are toxic.
- Prepared for flare-up or worse⌠Fire extinguisher of the right rating, e-stop for the laser and the air-assist/extraction, fire blanket, âŚ
- Other safety equipment like laser-safe glasses rated for your laser type/wavelength, enclosure to keep the laser beam contained in the event of reflectionsâŚ
Is your material flat on the metal plate you mention or raised up on a honeycomb bed or the IKIER H1 Laser Bed? Since the laser is vaporizing material you want that material removed as quickly/efficiently as possible by both having the material raised up and by using airflow (a combination of air assist to blow removed material away from the cut and an extraction hose with a fan to get the material/fumes out of your house (at best they smell, at worst they are toxic)
How did you arrive at the combination of speeds/power to use when cutting? Did you use the material test option under Laser Tools/Material Test to generate a grid with varying speeds/power to find the âbestâ combination to use/least amount of charring? You can experiment with multiple passes if that looks to provide a better result.
The answers to those will help the community provide you with better guidance/ask questions to understand your setup better.
Some other thoughts⌠3/4 pine is on the thicker side of material for a diode to cut⌠you likely will need more passes (the material test will help in choosing the best combination of speed/power/passes; Charing is inevitable - you are vaporizing wood and if multiple passes are needed it will be worse, especially with an intricate cut. Perhaps there is an alternate approach to achieve the interlocking design you are looking to do that might be simpler?
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Hey⌠thanks for the input!
Yes to your suppositions, however coming up to speed on Lightburn fairly rapidly.
The laser can get thru the 3/4 pine in two passes on clean grain⌠more with resin / knots. It definitely packs a punch.
I am doing the suggested work arounds by running the job over and over again manually so that lightburn doesnât overcook a particular area.
Still looking for an automated solution where it runs each pass IN FULL before repeating any particular cut.
So still looking for a suggestion on making a macro, or perhaps a software update to make this an option if anyone can help with that?
Yep definitely on a raised honeycomb with full air assist. The setup is on a covered deck so plenty of ventilation. I got my cut settings using the material test. Obviously given the variability of natural wood, they are just a guide and the results do vary a lot.
Thanks for your input but I really donât understand the relevance of what you are saying. Why would you run two completely different materials at the same settings?
I donât think you understand my issue at all. I am just asking for a setting where lightburn will do each pass in succession⌠complete the WHOLE PASS before repeating a cut so as to not overheat a particular area. Thatâs it.
Either a setting, or a software update or a macro. Anything to make it automated.
If you could suggest something for that, it would be a lot more helpful. Thanks!
PS: for those that think I think someone designed software to deliberately torch peoples houses, I will now add a winky face to the thread title. 
PPS: Well I would if I could edit the original post⌠but it wonât let me.
I donât, because I test the settings before I use them.
Point is, should I apply those settings to plywood anyway, I am wholly responsible for my chosen settings.
Pretty nearly every response in this thread has suggested different and generally better ways of accomplishing what you want, if what you want is even possible with the laser you have.
Two suggestions, for whatever theyâre worth:
- Learn from folks with experience in the field
- Change your approach based on new knowledge
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At the time, I didnât really understand what you were suggesting. This is EXACTLY what I need.
Thanks so much!
I believe I have what I am looking for with the relatively ânewishâ (as of version 1.2) sublayer settings. No need for duplicated geometry or manual re-runs, (i.e. The subsequent layer runs on itâs own without having to hit play. )
Someone did suggest this above, but I didnât understand the response at the time. So I put a link to the training video in this post for others having the same issue as me.
- Each pass runs in sequence
- No repeat cuts until the sublayer is done.
- Plus you get to tweak each layer like moving the z axis and adjusting speed and power settings. Perfect!!
- I am now going to mess around with lowering the z axis and decreasing the power for the clean up layers to help with charring as suggested by a helpful chap above.
Thatâs great that it indeed was what you were looking for.
Note that youâd typically mark the post that contains the solution as the Solution post.
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