EXT - Rastering Double Vertical Lines?

[Dave Fifield]

Hi Folks,

My 45W Epilog EXT has started rastering double on vertical lines all of a sudden. It's weird. I tried several firmware versions (1.0.1.4 thru 1.0.1.6) and tried it on WinXP and Vista, and it does it everytime. I swear it didn't use to do this.

Here's some pictures showing the issue - right click them to see/download the high resolution version. This test file was drawn as a single 0.5pt line rectangle in Corel Draw. You can clearly see that the laser rasters two lines separated by an obvious gap (only on the vertical lines, not on the horizontal ones). This issue shows up as extra-wide characters and fuzzy photos when rastering those things - not good!







This one is XP with f/w version 1.0.1.4 in the laser - same...


I went back to some earlier test work from a few weeks ago and looked at it closely. Lo and behold, this shows the same problem - I just didn't spot it then. The following are a couple of photos of the laser output of a single "dotted" line on a piece of acrylic that I did back then. You can see that the vertical line lengths are different and when you view the high resolution file, you can clearly see that the laser is rastering the 0.5pt line with a small X-axis shift depending on which direction the head is moving (L to R vs. R to L).





I did an archive search and found a couple of instances where people had X shifting problems with their lasers, but I didn't see anything exactly like this.

I cleaned everything inside the covered gantry - it didn't make any difference. From the fact that it's the same with different drivers and firmware versions, I would say this is a laser hardware problem. Oh, and this is with the speed nowhere near 100% - it's at 50% for the wood veneer rastering and at 60% (as I recall) for the acrylic rastering, and remember, it never used to do this. The X axis belt looks like new still, and it seems to have an automatic tensioning device at one end, so I'm loathe to start messing with it.

Does anyone have any insight into what I can try to get this fixed this weekend? Obviously, I'll give Epilog tech support a call on Monday, but I really need my laser working 100% today if possible. Peck, are you around? Any ideas for me?

Thanks in advance,

[Dan Hintz]

Tickle voltage set too high? Leading/lagging settings need adjusting?

[Dave Fifield]

Peck - are you around? Any ideas for me?

Cheers,

[Frank Corker]

That's really weird Dave. Even the line seems to have a different type of style. I wonder if it may have something to do with Corel, try this cdr file and see if it still happens. I don't know if it will but it might be worth a try I am using X3 and saved it in xp, if you don't alter it and just engrave it, see what happens.

[Rangarajan Saravana kumar]

Hi Dave,

Did you try to adjust any setting in epilog settings - laser match settings

Kindly go thru the manual and see the laser match and play a bit to get a proper settings... I have my legend 24 EX and solved this..


Dont thing any problem in driver.. upto my level of laser engraving

I think techsupport will be there to have a greatlook to solve your issue.

Regards,
Saravana kumar
Microcraft technologies

[Rob Bosworth]

Dave, did your machine do the double lines by going around the part twice, or does it go around the rectangle only once and give you two distinct lines?

[Peck Sidara]

Sorry I missed your posting Dave. I wasn't around this weekend-beautiful weather meant I was outside doing yardwork and stuff.


I'd recommend keeping the latest firmware/driver installed and copy/paste your posting and email tech support prior to calling. Some thought on possible causes:

*Calibration issue in x-encoder match or laser match.
*Possible cracked/delaminated lens or mirror causing a split beam only visible in the x-axis movement.
*Alignment off causing a deflection of beam producing 2 distinct beams.
*X-axis components related (something needs replacement or tightening)
*Laser source.

[Dave Fifield]

Thanks for the replies chaps!

Rob - nope, it does this in one pass only. If you look at the high resolution version of the acrylic example (which was drawn in Corel Draw as a single 0.5pt broken (dotted) vertical line) you can clearly see that it's drawing the line in two places, one when the laser head is moving left to right, and the other (offset in the X direction only) where the laser head is moving right to left. You can see each individual laser strike if you look closely!

Peck - Some creative ideas, thanks! Hope you enjoyed the great weather! Yesterday was very nice here too, and today we're due for a scorcher!!

*Calibration issue in x-encoder match or laser match.
- This is a possiblility which I'll investigate
*Possible cracked/delaminated lens or mirror causing a split beam only visible in the x-axis movement.
- Vector cutting works beautifully, and is clearly just one beam, so it's not this. Also, because you can see the two separate laser strikes L-R and R-L as described above, it's not this.
*Alignment off causing a deflection of beam producing 2 distinct beams.
- Not this - there's only one beam - see above.
*X-axis components related (something needs replacement or tightening)
- This is the most likely candidate IMO. I thought the X belt had an automatic tensioner on it? If it has an adjustable tensioner, then this could well be the issue. What's the recommended belt tensioning procedure? That, or the belt has developed a little backlash due to wear, or, as you say, some other X related component needs servicing. Could it be a loose belt pulley on the X motor?
*Laser source.
- The laser tube is almost new...and there's evidence that the laser beam is still just one beam and nicely focussed - see above.

I'll give the support guys a call and see what they say. Thanks again for your help.

Cheers,
Dave F.

[Michael Hunter]

If the EXT is the same as the EX, then the X-belt tension is only semi-automatic.
There is a sprung lever that sets the tension (far left-hand end of the cross-beam on the EX), but then the lever should be locked by tightening the screw.

The approved method according to my local Epilog distributor :
1 Loosen the screw to allow the spring to tension the belt.
2 Move the head from side to side a few times (by hand).
3 Tighten the screw to lock the tension lever.

Could be just that you have a screw loose

[Dave Johnson29]

the other (offset in the X direction only) where the laser head is moving right to left. You can see each individual laser strike if you look closely!

Dave,

If tech support have not yet resolved it for you, Peck's comment made me think. Try turning the artwork through 90deg and see what happens. That would eliminate Corel if it still does it.

[Dave Fifield]

Saravana hit the nail on the head! What a clever fellow!!

It was indeed the laser match value. It needed changing after I put a new tube in a short while ago. Was +7, now is -1 and everything is back to normal, thanks to Ian in Epilog's famous technical support group. He went right to the correct answer first time!!

So, +1 for Epilog's great support! Please tell them thanks from me when you bump into them Peck.

Cheers,
Dave F.

[Rangarajan Saravana kumar]

Hi Dave,


Happy to hear that your machine is back normal

All the experience we got from here only, kudos to SMC


Rgds,

Saravanakumar
Microcraft technologies