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Kellen Haines
07-07-2014, 9:18 AM
New to the forum. I've been having an issue engraving using Lasercut 5.3 with a Hurricane Katrina E laser. The issue occurs around the edges of objects and letters that are being engraved on all types of materials. I have attached a photo of what is happening. To me, it seems like the laser is using more power when it first fires to start the engraving, as it is deeper into the material around the edges. Anyone know what could be causing this? Is there any setting I can change within Lasercut?

Bert Kemp
07-07-2014, 9:54 AM
I'm having difficulty seeing were your problem exists, maybe a better picture with an arrow pointing it out.
Is this an engraving or is it being cut out, looks like a cut out to me.

Ross Moshinsky
07-07-2014, 10:00 AM
Probably your scan gap. You're probably engraving at 150-300dpi and you need to engrave at 500-600dpi.

Kellen Haines
07-07-2014, 10:33 AM
This is an engraving on 1/8" black acrylic. It really doesn't matter what type of material I am engraving on, I get the same effect on glass. If you look closely at these pictures, especially the picture with the letters, the edges around each are engraved deeper than the rest of the letter. I'm not sure if this has anything to do with scan gap or not, but the insides of the letters and tree objects is perfect.

Kev Williams
07-07-2014, 10:56 AM
I'm pretty sure there are acceleration and deceleration settings (and others) that can be adjusted to compensate for this problem-- but it will take someone with more knowledge than me to explain how I'm afraid...

here's a screenshot of some of the default parameters for my Triumph via my PHCad engraving software (everything is grayed out because the machine's not connected)-- I've never messed with any of my settings, but I haven't had to. You should have a similar list of parameters, and I'm sure some adjustments may help.

But like I said, WHICH to adjust, I haven't a clue! (sorry)


http://www.engraver1.com/erase2/triparam.jpg

Clark Pace
07-07-2014, 12:17 PM
Look like a possible rverse interval problem. What do you have that set to?

Robert Walters
07-07-2014, 12:45 PM
You should put your machine in your profile so we all know what you are running.

I wonder if that is backlash...
Machine on at the "READY", grab the head, does it move back and fourth slightly?
Are your belts snug?
Anything feel loose/worn?

Kellen Haines
07-07-2014, 12:52 PM
@Clark...I'm not sure where or what that setting is? I'm using Lasercut 5.3

@Robert...thanks, should be taken care of. Everything seems snug and nothing loose or worn. What is this backlash you speak of?

David Somers
07-07-2014, 12:52 PM
Kev,

Am I misinterpreting his photos? It seems like the edge of the image may actually be an outline in his graphic that is being run with different settings, perhaps a vector cut that is not set strong enough to cut deeply into the surface. The rest of the image is actually the engraving settings? He may not be aware the outline is there?

Dave

Kellen Haines
07-07-2014, 1:09 PM
The graphic that I am engraving is a solid black and white TIFF file. Its only one layer within lasercut, so there aren't multiple settings.

Kev Williams
07-07-2014, 1:57 PM
There's no vector cut, it's all raster-

I don't think it's a typical backlash issue-- backlash shadowing usually favors one side over the other. It's the result of the laser firing in a different position on the left-right pass than the right-left pass. This can be compensated for in the software.

But in this case there seems to be equal shadowing on both sides. Of course, the equal appearance may be an illusion...

Best test to see if it IS just a backlash issue is to run one of those jobs at 1/2 the speed and power of the first job. If it is a backlash issue, the edge issue will diminish quite noticeably at the slower speed...

Clark Pace
07-07-2014, 3:00 PM
When I get back to my machine this evening I'll see where it is.

Kellen Haines
07-07-2014, 3:01 PM
Here is a comparison of settings. The number on the right was engraved at 400mm/s, 30% power, 0.05 scan gap. The number on the left was engraved at half speed and power, 200mm/s and 15% power. Obviously, the laser is firing with more power around the edges of the numbers. Any clues?

edit: The second photo shows improvement, I just lowered the speed. I engraved it at 100mm/s, 30%power, 0.05 scap gap. Lowering the speed definitely helped, but still not good enough.

Kev Williams
07-07-2014, 3:45 PM
Then I have to stick with it's NOT a backlash issue. I'm sure adjustments can be made, hopefully someone has a suggestion or two...

Matt McCoy
07-07-2014, 5:33 PM
Can you post the original files? Is the fill the same color as the stroke?

Kellen Haines
07-07-2014, 6:10 PM
Here is the PNG file I've been trying. It was originally created in Illustrator and exported as a .png file. There was only fill color, no stroke.

Dan Hintz
07-07-2014, 7:54 PM
When was the last time you did an alignment?

Is the carriage and/or lens loose in any way, shape, or form?

Bill George
07-08-2014, 7:52 AM
Is this a new laser and if so has it ever cut or engraved correctly? I agree with Dan, check for loose set screws on the pulleys, mirrors and alignment, lens and / or carriage.

Kev Williams
07-08-2014, 2:57 PM
Here is a comparison of settings. The number on the right was engraved at 400mm/s, 30% power, 0.05 scan gap. The number on the left was engraved at half speed and power, 200mm/s and 15% power..

About this hollow 6 that didn't etch- At 200mm/s and 15% power with a 75 watt laser, the laser should've had PLENTY enough power to etch the interior of that 6, but there's not a mark on it, except the edges. That's not a mechanical problem....

http://www.sawmillcreek.org/attachment.php?attachmentid=292498&stc=1&thumb=1&d=1404759504

Dan Hintz
07-08-2014, 4:22 PM
About this hollow 6 that didn't etch- At 200mm/s and 15% power with a 75 watt laser, the laser should've had PLENTY enough power to etch the interior of that 6, but there's not a mark on it, except the edges. That's not a mechanical problem....

http://www.sawmillcreek.org/attachment.php?attachmentid=292498&stc=1&thumb=1&d=1404759504
Wait a sec, I thought the first one was simply edge-engraved. If it was meant to be filled, but didn't engrave that way, I would suspect either the tube is losing gas or the high-voltage supply is giving up the ghost.

Matt McCoy
07-08-2014, 9:00 PM
You get the same effect with both PNG and TIFF images? Can you try a vector image?