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R. A. Mitchell
06-07-2008, 10:31 AM
Looking for help diagnosing a problem. Engraved a stainless keychain fob using cermark on an Epilog Helix 75watt, 600DPI, 100S, 80P. The laser baked the cermark in well, but the text lines came out wavy.

I realized the movement of the head could cause some trouble, so I taped the fob to the table before engraving at the top of the fob. When the text at the top was wavy, I thought one piece of tape might not have been enough, so I flipped the piece and engraved the same image on the reverse of the fob, this time taping it at the top and the bottom. I was surprised to see that the same waviness was in the text on the second try (not pictured).

The other strange thing is the waviness is only in the top portion of the fob. If you look at the attached picture, you'll see the "LUV TIRA" is distorted, but the rest of the image cut well.

Any ideas?

Thanks!

Rob

PS - When I scanned the image, I inverted the colors to better show the text. On the original piece, the engraving is the typical black you'd see with cermark.

Richard Rumancik
06-07-2008, 10:47 AM
I suggest you check belt tension. The only thing different about the top line is the length of the stroke. Plus the waviness is likely more noticeable on the text than the heart.

On short strokes hysteresis (slop, backlash) in the carriage assembly will show up a lot more readily.

You can do the tests on wood or acrylic. It is a good idea to tape your part down, however. Lots of people don't realize that air movement, carriage vibration etc can jiggle the part around.

Phyllis Meyer
06-07-2008, 10:52 AM
Good Morning,

Cleaning the encoder strip should do the trick. Distilled water on a Q-tip (unless someone else has a better magic potion). Just check that strip because a little dust, dirt...could distort the text & images. Good luck and have a great day!

Sincerely,
Phyllis:)

David Fairfield
06-07-2008, 11:59 AM
Another possibility, since you are using 100 speed, you're adding momentum and basically increasing the G forces acting on the laser head.

Try slowing down and lowering power accordingly, that plus the other suggestions about holding the part steady, belt tension, and cleaning the encoder should work.

I'm also assuming your laser is on something solid, not a shaky table (voice of experience) :o

Dave

Peck Sidara
06-07-2008, 1:44 PM
Rob, try this:

http://www.epilogfiles.com/flashvideo/techtip_linearencoder/techtip_linearencoder.html


If that doesn't work, try tighting your x-axis belt a little bit.

Turn machine off, unplug power
Remove left side cover
Look at left side of I-beam for x-axis belt tensioning system. It's really easy to find; there's a pulley, bracket, spring loaded tensioning system and a Phillips head screw that you loosen for the bracket to adjust in and out.

Before you tighten the belt, get a feel on how tight the belt currently is; adjust accordingly. It shouldn't be too loose or too tight.

HTH,

Bill Cunningham
06-07-2008, 8:20 PM
I agree with David! don't know what the wattage of your laser is, but usually 100 speed it too fast for cermark.. I find that slowing down the machine, and 'burning' it in may not only give to a better mark, but eliminate any funny stuff from the turn-time lag or flex, or G-force

Frank Corker
06-08-2008, 7:24 AM
I'd go for the encoder strip issue. I had a similar incident and for me that was the answer.

R. A. Mitchell
06-08-2008, 12:50 PM
Thanks for all of your recommendations, but I'm still having trouble. Cleaned the encoder strip, tightened the X Axis belt, and same problem. Tried different areas of the machine, and same results.

I did my tests on a scrap wood block, and while not as noticeable as the keychain, the curvy lines were the same.

Next step - maybe it's the file. Anyone interested in burning a piece of scrap to see if you get better results than me? I'm running Corel 11. If you're interested, please PM me and I'll e-mail you the file (it wouldn't load to the message board - 360kb file size).

The font I'm using where the lines are wavy is Lucida Console.

Thanks!

Rob

Doug Griffith
06-08-2008, 1:40 PM
What happens if you rotate the file 90 degrees? I'd run a sample for you but am away from my machine.

Scott Shepherd
06-08-2008, 3:25 PM
To me, it looks like what Epilog calls "Shifting" and it's something that caused me a lot of problems.

Try this- on both sides of the graphic, off your actual item, draw a vertical line. So you'll have your graphic and to the left and right will be a black line, thick enough to raster and not vector cut.

So it'll look a little like this :

| Hi |

except the lines are solid and run all the way down the sides.

Try that and see if it solves the problem.

R. A. Mitchell
06-08-2008, 4:13 PM
Doug,

I followed your suggestion and the engraving came out perfect. I didn't try what Scott recommended (placing vertical lines outside the print field), but the changed orientation made the head travel much further on the X axis, so I assume Scott's suggestion would work, too.

This is the first time I've been really disappointed in my Epilog. This keychain was something for me, but it would have really hurt if this was a one-shot attempt for a paying customer. I thought the whole servo motor and encoder strip deal was specifically to address this kind of accuracy. I have a few people who have talked to me about small engraving jobs on iPods and the like, and this makes me very nervous about taking them. Not a good feeling after plowing so much money into a piece of equipment!

David Fairfield
06-08-2008, 5:06 PM
just curious if you tried a slower speed, say 35% or so, and if that had no effect?

Dave

R. A. Mitchell
06-08-2008, 7:37 PM
I didn't try the slower speed. Given my results from the orientation change, I would expect the slower speed would probably help, too. Slowing the speed is a disappointing requirement from a piece of equipment that is promoted as fast and efficient. In the big picture, I suppose a slower speed for a one-off small engraving job isn't a huge productivity issue. Just goes to show the importance of learning the limits of your equipment.

R. A. Mitchell
06-09-2008, 7:50 AM
OK. Still stumped.

Went to bed last night pretty angry at my laser. Got up first thing this morning to run a few callibration tests. Cermark and steel is a pretty expensive test, so I instead ran 2x2 sections of poster board on 600DPI, 100S, 16P.

First test was a series of verticle 1/2in .5pt lines, single, and then double separated by 1/16 in. I ran the test at various places on the table. All of them looked fine.

Next I ran a few "LUV TIRA" lines in Lucinda Console, 10 and 6 pt. Ran samples at various places on the table. All looked fine, even under magnification (10x loupe).

So I'm back to where I started. I don't want to unfairly disparage Epilog or my machine. At the same time, I don't know what went wrong with my keychains, so I'm reluctant to start marking on metal again. I'm going to start working with Epilog tech, but I'm wondering if anyone out there has other ideas for tests so I can figure out what is wrong.

Scott Shepherd
06-09-2008, 8:25 AM
Robert, this may not be your issue at all, but I'm going to explain it the best I can (which will be poorly at best). Our machine had similar problems, but it may not be your issue at all, so take what I say with a grain of salt, since we could be talking apples and oranges.

Doing a bunch of straight vertical lines in a row won't show you anything. The issue is when and where the burn starts. I'm not sure how to explain this, so stick with me. If you have text that's 1/2" wide, 1/2" tall, then the head is swinging back and forth over the same place and the laser is firing at about the same times, depending on where the text starts. However, if you place a small line, 1/8" high, vertical line, about 4 inches to the right of that text, on the same y-axis center line, then it'll start burning and as it gets to the middle of the text, it will have to swing over and start engraving that line as well as the text. Once it's finished, it'll change it's stroke again and be only the text.

That's where my issues happened. So that's a better type test, where the stroke changes in the middle of something, not where the stroke stays the same.

Try this file on a piece of plastic and see what happens. This file has the graphics towards the middle of the table. Move them wherever you want, but the most flex in the machine in when it's in the middle of travel on the y-axis.

This file is actually a test I used when I went laser shopping the 2nd time.

I hope I explained it well enough, and again, I certainly hope it's not the same issue I had. I hope it's something simple and they resolve it quickly.

R. A. Mitchell
06-09-2008, 9:11 AM
Steve,

Thanks for posting the test file. Is it in a format compatible with Corel 11? I haven't upgraded Corel yet, and I'm having trouble opening your file.

Thanks,

Rob

Scott Shepherd
06-09-2008, 9:20 AM
My mistake, I forgot you said V11.

Here ya go- give it a try.

David Fairfield
06-09-2008, 9:34 AM
IMHO Rule #1 of messing with lasers is keep the frustration in check. Now that my laser and I are on friendly terms, we can work out any problems, but it wasn't always that way! :D

I only use the 100% speed setting for simple cuts or coarse work where some "squiggle" won't make a difference.

I start my tests at 50%P 50%S until I zero in on a combination that works optimally with the design and material. Murphy's law, an untested p/s/f setting will always produce crappy results.

In most cases I can't use 100% speed, but its not anything to get frustrated over. Try running a new Porsche at 100% speed all the time and see what happens :eek:. And they cost a hell of a lot more than a laser. :p

As long as I'm not hovering over the laser while its operating, I find a 50% difference in speed does not significantly effect productivity.

Dave

R. A. Mitchell
06-09-2008, 9:50 AM
Dave,

I understand your point. My view, though, is when you buy a powerful laser on the basis of the additional speed and productivity you gain by working faster, and then find out that you have to work at a rate consistent with a laser at half that power, then your pocket has been picked for the premium paid.

Please note - I'm still trying to figure out my problem. I'm new enough where user error is more likely than machine error. Notwithstanding, I've been around long enough to know that you have to figure out the root of problems quickly to get to a solution or you wind up living with regret for a long time.

Rob

Rob

Scott Shepherd
06-09-2008, 9:55 AM
In most cases I can't use 100% speed, but its not anything to get frustrated over. Try running a new Porsche at 100% speed all the time and see what happens :eek:. And they cost a hell of a lot more than a laser. :p

As long as I'm not hovering over the laser while its operating, I find a 50% difference in speed does not significantly effect productivity.

Dave

This is where it gets crazy for me. You know, those dealers aren't running demo's at 50%, their brochures don't show their top speed at 50% or show a note or disclaimer that says you'll be running the majority of jobs at 50-60% speed. I think it's unethical to boast of speed, yet when it comes down to actually using the machine on non-demo stuff, you have to run it at 60%.

I can say that my quality doesn't change with speed. Same quality at 100 speed as 50% speed.

Also, it can get really tricky, as you hit it right on the head, if it's a smaller job, more often than not, the cycle time will be less with 70% speed than it is with 100% speed. So in some cases, it's actually faster to run it slower.

With all this type of stuff happening, is there no wonder why it's so confusing? :confused:

Peck Sidara
06-09-2008, 10:22 AM
Rob,

This is getting ridiculous. You buy a higher powered laser for more production, to have the ability to cut thru thicker substrates or for specific applications. You're having this problem because there's something going on with the x-axis. Contact our support group to trouble-shoot and get it fixed.

Rotating the image took care of the problem, tell tech support that as it may be helpful in their trouble-shooting.

I jumped in over the weekend as tech support was closed. They're open now and should be the first point of contact.

It has nothing to do with what others have suggested/indicated or may lead you to believe.

YOU CAN RUN THIS JOB AT 100%, NO PROBLEM. You will not have to slow the machine down to 35% or 50% for this job to come out perfect.

Call tech support. If cleaning the encoder strip and tightening up the x-axis belt doesn't help, it may be a faulty x-axis flex cable or a dirty encoder reader, dirty x-motor cog, loose y-axis component. Something along that line.

303.215.9171, press 1.

If by chance I'm completely wrong (it wouldn't be the first), I'll wear the dunce hat for a week.

Either way, keep us posted.

R. A. Mitchell
06-09-2008, 10:31 AM
Peck,

I'm the first to acknowledge that I didn't give Epilog tech support a shot at fixing this yet. Just poor timing with the weekend. I'll be on the phone with them soon. I'm a newbie trying to figure out how to run an important job. I have learned a lot from this forum, and greatly appreciate the free advice from people more experienced than me, but I also know I have much more to learn.

Rob

R. A. Mitchell
06-09-2008, 11:30 AM
Peck,

Got through to service, went through some more diagnostics, and I should get parts tomorrow.

When I started this thread, I wasn't trying to begin any crusades. I just want to figure out how to run a job. To that extent, I don't think posting a blow-by-blow tech support log is beneficial to anyone. I'll let everyone know when we've fixed the problem - that's all anyone on this forum is really interested in, anyway - but for now I'll stick with Epilog's very responsive tech support.

Thanks again to everyone who has tried to help,

Rob

Scott Shepherd
06-09-2008, 6:42 PM
This is getting ridiculous.

Peck, I've read back through this several times, what's getting ridiculous? I think he got good advice. He was down on the weekend and asking for opinions. People offered up their experiences. I think one person said they start their machine at 50S and work from there, one person asked him to turn the graphic sideways (good advice), and I stated clearly that my experience may not be the same as his, but it's what I had seen on my Helix.

Not sure where the ridiculous part comes in.

When tech support opened, he called them. A batch of parts is on the way and let's hope that solves his issues.