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Scott Winstead
06-06-2009, 7:21 AM
I'm engraving a 8"x10" piece of brass colored Rowmark - it has a picture, some lines of text, and then a large logo. I've done this type of laser engraving many times over the past several years with no issues.

Last night, I noticed some ghost engraving at the both the beginning and end of the lines (almost like a carriage return). Needless to say, it has ruined the engraved piece of Rowmark. The ghost engraving is faint - it's not penetrating the Rowmark but it looks like "rub marks" from mishandling the Rowmark.

I cleaned all of the lenses and then fired the laser back up and had the same problem. Any ideas? This is the first time that I've had this type of problem and am perplexed.

Thanks!

Rodne Gold
06-06-2009, 10:44 AM
The trickle or tickle voltage is set too high on your machine , phone the agents and ask em how to set it lower - often involves just changing a dip switch or jumpers on your main board.

Chris Hernandez
06-06-2009, 11:05 AM
Could be that you are getting some reflection from the metal. Try masking.

Scott Shepherd
06-06-2009, 1:08 PM
It's not metal, it's plastic.

Michael Hunter
06-07-2009, 6:14 AM
I got this sort of thing when the X-axis motor was failing.
It ghosted on jobs occasionally, but later started slamming the head into the end-stops at which point it was clear that something mechanical had gone wrong.

william kennington
06-08-2009, 4:46 PM
I have a pinnacle machine and had the same problem. Turned out to be the trickle voltage problem. Reset the dip switches and works perfectly. found out how to do it by researching this forum

Jason Lippert
06-09-2009, 1:51 PM
Is this photo a tickle problem? Had these badges come out a little funny, so I took a photo planning to post it. (Someone beat me to the topic, thanks:))
There is also a change in engraving where the different rows of text are staggered. If these photos are too small to see the problem I can post a zip with large versions. I hope this is a tickle problem, at least people know how to fix that easily.

Mike Null
06-09-2009, 6:39 PM
In my opinion you have two problems. A focus issue and and too much power.

I have encountered both with some frequency and the culprit is usually focus. More accurately, the problem is probably warped laminate. But on you first photo it looks like too much power.

The other thing that can occur with too much power is distortion of the material causing an out of focus condition.

The good news is, I don't think there's anything wrong with your machine.

Frank Corker
06-09-2009, 7:36 PM
I agree with Mike, my thoughts are that you have too much power which is why the heat has distorted the gold part. You might try putting a piece of transfer tape over the top and see if that helps.

Dan Hintz
06-10-2009, 1:27 PM
I don't know, guys... there's a very definite horizontal line in the middle of the entire text (just above the crossbar of the 'H' for reference) that is quite crisp. I would think too much power wouldn't allow for such crispness anywhere, particularly near such a large HAZ as the H's crossbar creates.

But I could be wrong...

Scott Shepherd
06-10-2009, 2:07 PM
I think this is a case of shifting. Try putting vertical lines, maybe 2 pt thick, on each side of the finished part and running it again. So it'll have the normal graphic and then running up and down the left and right edges, maybe 1/8" over from each edge, you'll have a vertical line.

Run it as normal then. If it resolves the problem, it's a shifting issue that's the problem. I've lived through this exact problem.

Mike Mackenzie
06-10-2009, 3:31 PM
Looking at this picture it looks like the X axis belt is worn try tuning the system and see if this helps. Usually tickle issues will only show up in the ramping areas (outside areas left and right hand sides). Try moving this to a different location on the table and see if it improves. If it does you need to replace the X axis belt. One more thing make sure your lens plate and lens are tight your lens that is mounted to the plate could be loose. Sorry jason I thought this was regarding the ULS in the original post. It is possible that your X axis belt is the culprit.

Mike Mackenzie
06-10-2009, 3:38 PM
Scott,

Your description of the problem does sound like a tickle issue. How old is the tube in this system? There are some settings depending on the age of the tube that either can be set in the system or on the laser tube.

Scott Shepherd
06-10-2009, 6:34 PM
My reply was to Jason's photos. On Jason's photos, his issues are where the logo and text on the left stop. So it's full engraving, then it stops engraving full from left to right, and it picks up that bad spot, and then when it goes back to engraving text all the way across, the problem goes away.

Jason, try what I said with the vertical lines and see if that resolves your issue.

Scott, I apologize, I was answering Jason's post.