50W Fiber Laser Ghosting Issue on Stainless Steel Plate Engraving with EZCad2

[John Kleiber]

Hello All,

I am running a 50W Fiber Laser and getting what I can best describe as ghosting or shadow just to the left of my text. The material is stainless steel plate and I am using EZCad2.

Speed 300
Power 75
Freq 20

Start TC 100
Laser Off 75
End TC 100
Polygon TC 75

The shadowing seen in the image cannot be rubbed off... its basically a slight annealing.
fiber_ss_ghosting_issue_2.jpg

OOOO Advanced Settings
fiber_ss_ghosting_issue_3.jpg

I need some suggestions as to the setting I would look to adjust in EZCAD2 in order to lessen or alleviate the issue.

Thanks, John

[Gary Hair]

Not sure why yours are so different, my settings for the following:

Start TC: -300
Laser Off: 400
End TC: 150
Polygon TC: 100

Where in the marking field is this happening? I always try to center the design in the field and position the piece I'm marking to accommodate.

[John Kleiber]

I've got everything dead center.

Modifying my settings to yours changed the shadow from left to right side.

After about a dozen tests, my settings are currently the following ...

Start TC: 0
Laser Off: 0
End TC: 150
Polygon TC: 100

Also, I am not sure about the correlation between Start TC/Laser Off/End TC, but after I changed to your settings and then to my NEW adjusted settings, I had to reduce power by 25%.

At some point I will put the old settings back to see if in power or the effect of power on the material changes.

-John

[John Kleiber]

Thanks for the guidance Gary. Once I started making small changes based on your suggestion, the results were better than expected.
The stainless steel I am engraving on is a custom knife. Problem is, the knife is finished and the engraving needs to be perfect once complete.

The image does not do the engraving justice, but here is a close-up engraving on a peice of scrap SS.
The text was engraved, low and slow, then I followed up with a nice black annealing.

fiber_ss_ghosting_issue_4.jpg

[Gary Hair]

It looks very nice in that picture so it if looks even better in person you should be very happy with it! Nicely done!

Thanks for the guidance Gary. Once I started making small changes based on your suggestion, the results were better than expected.
The stainless steel I am engraving on is a custom knife. Problem is, the knife is finished and the engraving needs to be perfect once complete.

The image does not do the engraving justice, but here is a close-up engraving on a peice of scrap SS.
The text was engraved, low and slow, then I followed up with a nice black annealing.

fiber_ss_ghosting_issue_4.jpg

[John Kleiber]

Finished product...
fiber_ss_ghosting_issue_5.jpgfiber_ss_ghosting_issue_6.jpg

[Glen Monaghan]

Nice work, John! OOC, about how long did it take to engrave that?

[John Kleiber]

I did not make an exact note of the time, but I think engraving at 400 speed and 50% power, plus final annealing pass, total time was about an hour.

The final feel of the engraving is smooth as butter.

[Gary Hair]

Finished product...
fiber_ss_ghosting_issue_5.jpgfiber_ss_ghosting_issue_6.jpg

Wow John, that is beautiful!

[Glen Monaghan]

This is a gantry system?

[Gary Hair]

This is a gantry system?

Pretty sure it's galvo, you can't do that type of work with gantry.

[John Kleiber]

This is a gantry system?

It's Galvo.

[Glen Monaghan]

I was just thinking that an hour was a long, long time so assumed it must have been a gantry system. Wow, can't even begin to imagine how many passes that would be on a galvo!

[Kev Williams]

FWIW, I have my TC's at -30/190/400/250 -- I arrived at these settings by spending a couple of hours hatch filling various width text and shapes on black brass at zero power and examining the results with a loupe. The result at these settings was nearly identical burn everywhere, no blank spots, sharp corners, no thin or thick spots. While I'm not smooth as butter yet, it a far sight better than I was getting at the factory 50/600/800/500 settings.

I'm going to assume that all these machines will have their differences...

Haven't had a lot of time to fiddle with clean-up settings, too much work to get done!