PDA

View Full Version : Laser engraving question



Kim Vellore
10-02-2006, 1:39 PM
I have noticed this in my laser and would like to know if any of you folks have the same type of problem.

I sometimes engrave card stock like the thickness of a business card, what I have noticed is after engraving I find numerous holes in the card made by the laser. The laser sometimes puts out more power than requested at the start or end of the engraving line. For example I engraved card stock to look like roof of a building and it looks like it has taken a few bullets. It is not consistent. Is this the normal property of the laser and cannot be helped or are there other types of laser cutters that does not have this issue. I have a Epilog legend 24tt 45Watts

Kim

Keith Outten
10-02-2006, 3:20 PM
Kim,

I own an Epilog Legend that is about four years old now and I can't say that mine has ever done what you are experiencing. Unless someone else chimes in with a suggestion you might give Epilog Tech Support a call.

Sorry,

.

Joe Pelonio
10-02-2006, 5:01 PM
I have the same machine and have done card stock too. It's a delicate balance on the settings and focus. The material has to be perfectly flat on something other than an old vector grid. Rastor engraving is dots
and what you are getting is likely some too deep going all the way through. I saw that when experimenting. Try lower resolution, 200-300 dpi, and maybe slow it down and less power. I started with the laserlights settings and adjusted from there until I got it right, but can't find the settings now (only did paper that one time). There's also an adjustment to the "linger time" on the ends of each pass that could be an issue for you, check the manual (never played with that)

Richard Rumancik
10-02-2006, 11:45 PM
It does sound like the laser is creating the holes due to the fact that it has to decelerate the carriage, stop, and turn around at the end of a raster line. I think on my laser there is some amount of over-travel but I am not in front of the laser so can't say for sure. Can't say I have actually tried what you are doing.

But if you can't solve it some other (better) way, here is a possible work-around.

Add a phantom "border" say .004" wide on the left and right sides just a bit past the end of the "part". If you turn border into a bitmap (merge with your roof bitmap) then the "bullet holes" should move to the border lines and off your part.

This might not be the most elegant solution, as it increases job time and wastes a bit of material, but might work until you can come up with a better solution.

Kim Vellore
10-03-2006, 1:19 PM
Folks, thanks for all the pointers, it got me trying other options I did not think of.
Here is what finally worked last night. I switched to vector engraving and had a similar problem but had sharper lines, If I reduced the speed it worked better, but it was not a option because there were too many lines to engrave and it will take for ever. when I increased the frequency to 3000Hz (PPI) it worked best. I had to modify the power level but it worked. I tried to reduce the frequency but it got worse and the engraved lines had the dots show up like a doted line. A picture might might show this a lot better, I'll try to post one tonight.
Thanks again for all the help.