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View Full Version : Horizontal lines widen then narrow alternately.



John Kleiber
03-16-2017, 1:05 AM
Ran a test today on a scrap piece of SS in the middle of the laser bed for timing a laser job with Cermark.
When the run completed I looked at the Cermark lased on stainless and the technical diagram I marked had alternating width on horizontal lines.

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Settings:

Min/Max Power 60
Speed 300
Interval .07

After review of the mfg. website I surmised loose / dirty lens, focus, belts etc. Sent an email to mfg. asking if I was on the right track, but its after hours for them and will have to wait for a response.

At first I searched wavy lines here on the forum. But after a closer look they were more so alternating between wide and narrow and a little wavy in places.

Here is the problem illustrated....
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Tomorrow I will run various tests using different parts of the bed and vertical/horizontal lines to narrow down the issue.

First thing I will check is the lens because it just seems odd to me that the line is consistently wide then narrow over and over.

John Kleiber
03-16-2017, 12:39 PM
ok I figured it out.

I took apart the lens assembly and cleaned everything. Cleaned all rails with DNA and applied a light sewing machine oil to the rails. Ran unit to all extents of rails.
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Made test x/y diagram and ran test. Test good.
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Loaded original file with line x axis wavy/thickness issues and job. Fixed it!
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Kev Williams
03-16-2017, 2:40 PM
Chances are your lens or the lens housing wasn't quite tight :)

Jeff Body
03-16-2017, 5:19 PM
Chances are your lens or the lens housing wasn't quite tight :)

That was going to be my guess.

John Kleiber
03-16-2017, 7:32 PM
That was going to be my guess.

Kev/Jeff

The lens housing was super tight. I had to wrap pliers in electrical tap to protect the assembly just to get it apart.
I rarely laser wood or anything that puts out a lot of smoke or residue.
The inside of the assembly did not seem that dirty at all.
But then again, I guess one particle in just the right spot may have an effect.

Unfortunately I did 2 primary things; clean lens and clean and oil rails. I don't know which one did the trick.

You guys are more experienced, so lens cleaning has all the votes as the culprit.