Epilog choppy lines, bad engraving quality compared to Trotec

[Jason Saul]

Hi all - I have a Speedy 100 and a Fusion 40. I noticed, in cast acrylic, my Fusion has been engraving with a choppy, unsmooth quality compared to the Trotec lately. Trotec engraving on top, Epilog on bottom in the photo below. I adjusted belt tension, checked/cleaned all mirrors/optics, and greased the rail - and then tried numerous settings to try and gain a smooth engraving. Changing the dither to brighten or stucki helps - but it's still nowhere as buttery smooth as the Trotec (the Trotec is also a slightly brighter engraving as far as the grey is concerned).

Anyone have any experience with this? Any tips on how to work toward a fix? Have a big acrylic job coming up next week and I'm stumped. Tech support didn't answer the phone - it's Friday afternoon and all - so I thought I'd throw it out here.

:/

1.jpg

[Kev Williams]

Does the Fusion's driver have any type of photo or halftone mode, whereas you just print a photo as-is and the machine takes care of it?
If yes, then experiment with different grays, I use 70 or 80% black typically. My Gravo LS900 does the same thing as your bottom pic when just engraving straight black onto plex, but 70% black in photo mode and it looks almost sandblasted. Same for engraving glass. And try colors, basic green and cyan work pretty good sometimes.

If no to photo mode, or it doesn't work good enough for whatever reason, try using pure halftone or 'ordered' routines rather than Floyd or Stucki random types. Halftone some 70% black at a 30° angle, it may break up the laser firing evenly enough to help.

I've found that just using Corel's 'create bitmap' (in b/w) at 200dpi using cyan as the base color worked great on wine glasses.

[Jason Saul]

Thanks Kev. There is no photo/halftone mode in the driver, but I did try ordered dither patterns and 70-80% black - it helped a bit, however, it's still clear the engraving isn't as smooth as the Trotec. If I look closely, I can tell there is an issue I'm not resolving. I was told to check if the bearings are going bad - but I don't know how and tech support is closed over the weekend.

Does the Fusion's driver have any type of photo or halftone mode, whereas you just print a photo as-is and the machine takes care of it?
If yes, then experiment with different grays, I use 70 or 80% black typically. My Gravo LS900 does the same thing as your bottom pic when just engraving straight black onto plex, but 70% black in photo mode and it looks almost sandblasted. Same for engraving glass. And try colors, basic green and cyan work pretty good sometimes.

If no to photo mode, or it doesn't work good enough for whatever reason, try using pure halftone or 'ordered' routines rather than Floyd or Stucki random types. Halftone some 70% black at a 30° angle, it may break up the laser firing evenly enough to help.

I've found that just using Corel's 'create bitmap' (in b/w) at 200dpi using cyan as the base color worked great on wine glasses.

[Kev Williams]

I'll just say that I don't think bad bearings is your problem-- even with bad bearings, I don't think it would cause that any more than good bearings...

The pic below; I did this in Corel, Arial bold, 3/8" tall, started with 70% black and then the colors as listed. I then went to the Bitmaps tab and converted each to a 300dpi black/white bitmap, with dithered, 'apply ICC profile' and Anti-aliasing boxes checked. (Top one is just plain 70% black)

Note that every one produced a different dither pattern...

dithertest.jpg

I saved this as a Corel 10 file :::>> dithertest.cdr
This way you can open it and check it out, and use it to test engrave- One or more of them may fix your problem!

Try different resolution settings, I have good luck with 500/500

[Mike Null]

I am inclined to think it is a bearing issue.

[Jason Saul]

You've seen something similar, Mike?

I am inclined to think it is a bearing issue.

[Mike Null]

Yes, but not as severe as yours. I believe it's mechanical although you appear to be getting a sharp edge.

Have you moved the head across the x axis by hand? Usually, anything less than a smooth action indicates a bearing issue.

[Kev Williams]

My GCC's X rail bearing started spitting out bearing balls awhile back, it was so floppy-loose I was amazed it engraved anything, but it worked quite well considering. Once I put the new bearing in, it actually got worse because the bearings fit so tight against the rail. Every time the bearings left the rail or entered the rail it would create a noticeable 'thump'. Was like the rail had a serrated edge -- The bearings have since worn in thankfully--

However, checking is easy enough, do like Mike says, but remove the belt first if you can. Check for the feel of 'crunchy' bearings as you move it back and forth. Check for excess slop of the laser head; see if you can rock the head by rotating it back and forth, and also from front to back. There should be virtually no play when gently rocking/rotating the head. AND it should roll very smoothly across the rail. Don't pay much attention to the SOUND of the bearings, they can seem noisy but that's because they run nearly dry. --My LS900 will be 15 years old in a few months and I've never lubed any rail bearings. Even after all the miles on my X-bearing and rail, it has zero free play and rolls smooth as glass. But the bearings aren't particularly quiet

A note about lubricating recirculating-type rail bearings: In my GCC owner's manual it states the rails should be lubed with a light grease. When speaking with a rep with the bearing company I got a replacement bearing from, he stated these types of bearings should only be lubed with light machine oil, and only like once a year by lightly wiping oil along the rail(s). He explained grease being a no-no because the tolerances are so tight within the bearing that there's no room for grease, and once packed with grease it can force the bearing balls out of the housing!

Anyway-- good luck

[vic casware]

I wait with baited breath to see your fix for this
I've had my Fusion for 3 years now and the engraving on Acrylic
or Silver material has always been sub standard.
Last year it got really noticeable especially on the silver
so i did the same thing and tightened the belt a bit,
it did the same thing and mad things look slightly better,
But i ended up losing pieces of the teeth on the belt.
Anyway, got a new belt and now it's back to the same bad acrylic
and silver engraving, nobody has any solutions for me so far
so i look forward to your fix.

[Keith Downing]

Vic I'd just call up tech support. The best thing about Epilog is they have (generally) very competent technical support, free for the life of your machine. Might take a little back and forth to get a complex problem sorted out, but I think you'll have much better luck than waiting for someone w/ the same machine and same problem to come along with a solution here.

[Ross Moshinsky]

It's probably something mechanical but sometimes systems are just designed poorly and result in subpar results under certain conditions.

To test if it's the bearings, rail, or belt, slow the machine down considerably. If things look a lot better, it's one of the three.

To get better results I'd probably slow the machine down, use a bit less power, and put it out of focus a bit. It might not make it totally disappear but it should lessen the effect dramatically.

[vic casware]

Hi Keith,
I agree, I did call last year when the damaged belt issue began ant they were great help
but i usually have to start off dealing with the agent here in New Zealand and they contact the US,
Crazy thing happened yesterday, as soon as i posted i went back to my Helix to finish
a job i was running and the machine had died, fans were still working but everything
else was dead, luckily the agent had a Motherboard in stock so hopefully (when it turns up)
i'm right back to it.

[Keith Downing]

Hi Keith,
I agree, I did call last year when the damaged belt issue began ant they were great help
but i usually have to start off dealing with the agent here in New Zealand and they contact the US,
Crazy thing happened yesterday, as soon as i posted i went back to my Helix to finish
a job i was running and the machine had died, fans were still working but everything
else was dead, luckily the agent had a Motherboard in stock so hopefully (when it turns up)
i'm right back to it.

Interesting. I didn't realize they routed support differently outside the US. I guess it makes sense though.

I'd just try to get the email of someone who is especially competent in the support office and send issues questions to them directly. I've got a great contact that usually has my problems solved within minutes during normal business hours.