any chance you could post the LBR of this pattern?
i just want to understand the path order
it might matter
gimme a few let me look at it!
Thank you!
Ok so Bare with me
We dont need to CUT, we need to mark only
try this file in a bit of cardboard thats flat or⊠wood you dont mind engraving on
Must be nice and flat though so we can look at it
Your normal settings at top, rotated
Broken apart below
half speed bottom
There is some logic to my madness trust me 
Gil Test.lbrn2 (89.2 KB)
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Long post so if Iâm suggesting something already answered I apologize.
Looking at your latest test makes me believe you still have a mechanical issue with the waviness.
I know co2 lasers have a coarser beam than the diode I use, but the corners make me think it might be out of focus.
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I will run these tomorrow morning. Thanks for taking the time!
Well after a couple of days of calibrating, aligning, squaring, etc, I ran another ramp test and have the sweet spot in the middle of my 1/8" board, which honestly the sweet spot is close to that thickness anyway. Not sure what else I can do.
I will say that these pieces are quite small and the pics are zoomed and obviously poor quality. Other than the serrated edges that I am trying to fix currently, the pieces look pretty good to the naked eye. But I am a perfectionist and I do wish the cut was better overall.
Thanks
this might be whats compounding the issue but the test i sent will expose it. hopefully
Alright I ran those two tests. The only thing I changed was the power setting. I had to drop it to 10 in order to not cut through, although it still did in a couple places.
Test 1 - top two rows
Test 1 - bottom row
Test 2
I noticed also that the smaller the circles, the more wobbly and out of round they get. When I ran my calibrations and I cut out a large circle and checked its dimensions with my calipers it was round. I would like to clean the smaller ones up also.
I look forward to hearing what your thoughts are on these tests.
Thanks!
Now this is what i expected
even though the circles might be related i think this is a bit secundary atm
Now what differentiates the top row vs the 2nd one is your Layer 01 has a -0.064 Kerf Offset inward
and the 2nd Row does not have it
I believe now THIS value is what is creating the ripples, but i have NO idea why!
The 2nd test when you grow the size seems it dissipates most of the issue, but still present on BIG size with the -0.064 kerf
Maybe the Devs could take a look?
@johnjohn @rich @LightBurn
We proved machine is able to do it Right. but when kerf settings is on it does it wrong
However it does it wrong in a weird way taht might worth being identified.
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Good catch on the Kerf Offset. BUT I am not sure where the -0.064 came from. In the file I sent/attached the Blue (01) should be set to -0.0025 offset and the Black (00) should have been 0.0025 offset. It looks like in my original test file the Black one got zeroed out but the blue shows -0.0025. Also your test file comes up as -0.0025 on my end so maybe since the Blue (01) is supposed to be DEFAULTED to -0.0025 then maybe that overrides the kerf offset for every file I open?
Either way, it looks like the kerf offset could be the culprit 
I will zero the Offset setting and rerun a couple test cuts and see if that will be a temporary workaround so I can get some of my orders done. Based on the tests I donât think this will fix the smaller circles though.
I appreciate your help on this!
you already did but yes do try! and do try wih both settings you know are defaults
Again i dont know the WHY though
Alright I ran the test at 40 mm/s with BB and the serration is GONE. I know the test you had me do was the same test but it always seems that when I think I have something figured out, when I go to run some jobs I find that it is not fixed for whatever reason. I just wanted to do it on 1/8" wood to make sure.
I also did some testing with my focus. Not so much because of this issue but because I was noticing that the cutouts on the back/bottom of the pieces were smaller openings than the top which made me think that the sweet spot is actually below the board and not in the middle like it should be. So after some adjustments the pieces look much better now.
So now that I have a temporary workaround for the serrated edges and I have adjusted the focus, I just have the issue with the smaller circles, and the inner corners, especially with the small diamonds. This is not an actual image from my latest tests but the problem is the same. Could these round tips/corners be because I have the min/max cutting power the same? I know that LB can lower the power as the laser slows to make a direction change so that it does not burn too much as it slows>stops>accelerates. It would make sense by looking at these diamonds. Just a thought.
Good GOod
What I would suggest here though is tackling 1 variable at a time or you lose track of what is what
Without KERF settings at all - i would say you might be moving too fast for the size of the shapes
Physics still dictate how fast the machine can move the direction without physically shaking
In that size - same with small font - at times one has to give up speed for the sake of quality of shapes.
If it were to happen slower too i would think it has to do with some mechanical issue. But donât seem to be the case.
I agree with all of that.
I ran some tests at 40 mm/s with a Max power of 52.5 and then tested the Min power starting at 10 and going up until it would cut through at the corners which ended up being 20. Compared to previous tests I think the shapes are much cleaner, especially for how small and the speed. The tips/points are not a perfect point but obviously they canât be. I think the small circle even looks better now.
By the naked eye it looks almost perfect.
Hey is there anything further we need to do to get the Kerf Offset/Serrated Edges looked at by the LB team?
Thanks so much for the assist on this. I was starting to question my purchase of this laser.
They will ask, if i am honest i wouldnt know where to start
I have a few theories but is outside my brain paygrade!
P.S. is important too to know that they must 1st replicate it, i dont have a Co2 so cant
Thatâs because the mechanical errors have a more-or-less constant size that becomes relatively larger for smaller patterns.
For example, these are 1 mm, 2 mm, and 5 mm circular holes cut in paper layers with a 60 W COâ laser:
The 5 mm hole looks OK-ish, but the smaller holes are severely and consistently bent out of shape.
It turns out the gantry in the laser has a little wobble, particularly at a nominal cutting speed of 300 mm/s. Although the machine canât possibly go that fast around those circles and it definitely shakes while trying, larger features donât look all that bad.
The round holes in your pendants are only 1.5 mm diameter, so the remaining mechanical errors in your machine loom much larger. In order to reach âperfectionâ on tiny shapes, you must eliminate everything that can contribute to any uncommanded mechanical motion.
Being almost right gets it to âpretty goodâ, which is about where it is now. The next level requires neurotic precision concerning belt tensions & anchors, screws of all kinds, overall frame rigidity, and speeds-n-feeds.
Itâll definitely take your mind off all your other problems ⊠
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Normally I would go to that level. It is a sickness of mine 
To be honest if all my tiny holes can look as good as my last test then I call that a WIN. What bothers me even more though is when every once in a while the tiny holes are not centered. I get why. The same reasons you just mentioned. But it still pisses me off. LOL. I think what I will do is just slow those tiny holes down to like 20 and call it a day.
It may also be that the non-cutting motion (G0 moves in G-Code machines, maybe Idle speed in Ruida parlance) may be too fast for conditions. Depending on how far and in what direction the head travels from the previous cut to the next hole, the machinery slightly overshoots and wobbulates while the hole cutting begins slightly off center at a much slower speed.
Remember: everything is deeply intertwingled!
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