I’m sorry if I posted in the wrong area. This is my first.
My issue is with the lines in the center in the 3d engrave in the picture. It’s on both sides.
I have a Monport 50w non-mopa laser. I have my engraving down pat with 2d engraves. The lines do not appear on the 2d.
engraving:
Speed 3500
power 50%
Freq 60
interval .02
cleaning:
Speed 3500
power 30%
Freq 75
interval .01
What am I missing?
Thank you.
PS - My lens is 70 x 70.
Do you have some kind of air assist or vacuum to remove the debris from a previous scan?
Sometimes it’s possible to weld some of the debris back to the material. The other thing that cause strange lines is interval. Sometimes it can create something like a moire pattern.
An F100mm (70x70mm coverage) has a spot size of about 16 microns. If your scan interval is 20 microns (0.020mm) it might be an issue. You’re scanning step size is likely larger than your spot size.
These short lenses have a very very short depth of focus (dof), somewhere around 0.750mm. There are many on-line calculators that can give you a base line to work with, such as this one I use.
If you know or can find what source in your machine, you can get the beam size and M2 information.
Not confident on what’s causing anomaly to appear only in selected areas.
Thank you for the info. I do have a large vacuum fan behind it venting out the window.
What threw me off is that it only happened in the center.
No 
, same here.
I did a number of coins where the anomalies on one, are on one side, on another a different side. Many times I can change it by a slight change in interval.
Can you post the other side of the coin?
Hang in there, some great people hang out around here..
Maybe we should ask for assistance from @Albroswift or @Aaron.F, they do a lot with thier fiber machines and can probably make suggestions.
It looks in the same position as the other side. We’ll have to hang on until we get some extra brain power looking at this..
I don’t have anything else to add at this point.
I was seeing that center line even on doing a clean pass.
I really appreciate your calculator help. I did it real quick and changed my interval to .038.
That stepping in the center disappeared. I sanded this down a couple of times and ran blank engraving and cleaning passes. Lines have disappeared. So now I just need to do it a few more times and adjust accordingly.
I appreciate your help!
@RandomGuy, worth checking your Delay Defaults in the Device Settings. If they are all at 100us, those are the defaults, and it’ll improve the result if you adjust them.
The config files from Monport might hold the timing settings, but in some cases, they are in the BslCAD.cfg instead of the LmcPar.cfg
Can you upload both those files for investigation?
Very good point… wish I’d thought of it. 
As always, I suggest you follow @Aaron.F lead.
Here’s a great video on setting your timing and delays. If these are not set up correctly, you pay for it in the resultant image, as @Aaron.F advised.
Laser everything has a great group of videos on fiber and other lasers.
I don’t have anything technical to add, but I do like your coin design.
Thank you!
I tried finding those but didn’t find them in LB. When I got the machine, I tried using ezcad that came with it but I got nothing but errors. I just went through LB and did the set up for the laser that way. Did I do a big oopsie?
I got super lucky. I changed the interval and did the same coin again. Lines are gone.
I truly appreciate the help given!
Too high speed for small area, please check it in microscope. And remember lenses have a nonlinearity scale and beam power at angles.
