Troubleshooting: Laser Engraved letters are wriggly and distored

[Lamar Mullis]

Hey Folks,
First time on the forums. I have been reading through many posts and have been waiting patiently for my account to be verified so I can post.
I have an 80w Chinese World Laser. Have been working with it for 5 years. Replaced the tube last summer '10, and have had no issues with it whatsoever until 2 days ago. I was in the process of engraving 3 plaque plates and then moved on to about 12 trophy plates and 24 medallions. The engravings at first were great. Clear crisp letters- but since then have gotten repeatedly worse as the engraving went on through the day. Now most letters are squiggly and distorted. I have tried everything. All belts, mirrors, lenses, are tight and clean. I have done nothing differently than I normally do every day for five years-

Can anyone help?? Please, I have to finish these trophy plates by 5 pm today. I could go to the 40w, but I am much more comfortable with the "mama" laser.

Thanks for your ideas and suggestions in advance!

[Dan Hintz]

Pictures always help...

Squiggly lines almost always mean something is physically loose. Make sure the focal lens is glued into its mount. Make sure the mount is snug to the carriage. Make sure the setscrews on your pulleys are snug. Make sure the carriage is snug in its movement along the rail. Etc.

[Alexa Ristow]

Hi Lamar,

Dan is almost certainly right.

Jiggle all components by hand to try and isolate a loose piece.

Drop your speed way down and engrave onto a piece of waste material. if the squigles are reduced at a lower speed then you count on one of the focal elements being shaken at high speed

[Martin Boekers]

Distorted lines on my Epilog usually means a dirty encoder strip and/or reader.
You probably have stepper motors though not sure.

[Rodne Gold]

You didn't perhaps change your backlash compensation - if your laser has one
A picture of the output will help , especially a macro type close up...

[Lamar Mullis]

Hi Lamar,

Dan is almost certainly right.

Jiggle all components by hand to try and isolate a loose piece.

Drop your speed way down and engrave onto a piece of waste material. if the squigles are reduced at a lower speed then you count on one of the focal elements being shaken at high speed

**well indeed the squiggles are reduced when lasered at a lower speed..... now, to figure out which nut it loose is going to be the challenge of the day....I guess I will start with the lens and mirrors, and then move to the pulleys and belts.

[Lamar Mullis]

not sure about a backlash compensation setting.... I will print my screen and post it here in a few

[Alexa Ristow]

To follow on a bit from Rodney's post. In an eattempt to sort out corrupted firmware last week, I inadvertantly change acceleration and deceleration setting on our Rabbit 6090. The result was that at higher speed, the laser would cut a " wobble" when cornering hard. I inspected the whole assembly but could not find any errors. I re loaded the laser cut software to restore the factory defaults and ... problem gone. lesson learned is that the less obvious setting such as acceleration and backlash compensation can have a profound effect on the machines performance. I have now started hunting down better explanations of all the advanced settings.

[Mike Null]

Be sure the work is not moving on the table.

[Martin Coetzee]

**well indeed the squiggles are reduced when lasered at a lower speed..... now, to figure out which nut it loose is going to be the challenge of the day....I guess I will start with the lens and mirrors, and then move to the pulleys and belts.

I had the same problem and it turned out that the set screws on the X axis pulley were not tight enough, causing the shaft to slip inside the pulley. I discovered this by grabbing the X axis beam and tried to move it forwards and backwards by hand. This showed up the problem immediately !

[Lamar Mullis]

Success! After 2 days of total frustration last week, I came in this morning with a clear head. I went back to the lens nozzle. I took it apart again, and sure enough.... the ring that tightens the lens into place was loose, as well as the air tube connecter. Thank you all for your quick responses! I am eager to continue building relationships with all of you here on this great forum!!!