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View Full Version : New laser tube, new problems



bruce edwards
12-26-2011, 4:35 AM
Hi hope everyone is having a good holiday season. My laser tube on my Epilog Mini 18 went out after about 6 months of minimal use.
Epilog sent me another 1 and its under warranty so I only had to pay customs/duty/whatever of about $300 US dollars to get it out of
customs. Putting the new tube in wasn't so difficult. But the alignment...wow....after a couple of nights on phone with tech support, and
many hours of adjusting hex screws...well they are on vacation until the new year I believe...pictures are worth 1000 words..what the &%$#
is going on now?? :confused::mad::eek::(:mad: This is on black aluminum, 600 dpi, 100 speed 40 power. Siiigh....so much varying degrees of engraving, lots
of erratic engraving...blurry.. I cleaned all the mirrors, tried many different focus heights etc....all look terrible. :confused: The bottom portions of the
"g" letters are terrible, the "r" letters are all blurred, and the lower part of the 8x12 inch aluminum is much lighter than the rest. Not to mention
the horrible picture. (600 dpi pic) 217192217193217194

heres the same pic on 3.5x2 inch aluminum....this is costing me $ in lost business. I have to tell people I'm "too busy" and can't do
their orders...217195

walter hofmann
12-26-2011, 6:04 AM
wow $ 300 just for customes is a lot of money on a waranty item.
now I dont have a epilog but the beam alignement is pretty much the same on most laser.
1. make you a couple of hardboard ( 1/8 inch or so) in the size of your mirror holder and mark the center of the lense with a cross this is for the reason that you dont have to take out the mirror before adjusting
2. take some masking tape and tape one of this board pices exactly to the first mirror in the back across the laser tube
3. fire the laser short [pulse and see where the beam hits the board, it should be dead on the center , if not adjust the holder keep in mind that it is lots of fiddeling to get it right but with a couple try you get a feeling for it.
4. after the first mirorr is alligned you take the board from the first miror off and take another pice of board and tape it on the gantry mirror holder ( this is the mirror on theX axis)again exactly that the center cross is exactly center of the mirror
5. now comes the fiddle part you first put your gantry ( X axis ) in the closest to the laser tube possition and fire the laser with a short burst, if you lucky it will hit the board if it is not on the center you need to adjust the first mirror untill it hits the gantry mirror
6. after the gantry mirror is hit somewhere in the middle you put your gantry in the farest position still at the same site and hit the laser again if you are lucky again you hit the gantry mirror somewhere in the middle now you need again adjust the first mirror till you hit exactly the first laser point you have to go back and forth amny times to get it right. this takes care of the Y axis alignement
7. now you take off the board from the gantry mirror and put a pice of tape on the laser head mirror ( thats the hole on the lense holder on top)and put the gantry in the closest to the first mirror position
8. now you hit the laser with a short burst again and see where the laser hits the head mirror openeing ( thats the hole above the lens)
now you need to adjust the gantry mirror that the laser hits the hole close to center of this hole
9. now you put the gantry in the farest position still at the same site and hit the laser again this hit should be exactly where the first hit was from the upper position what mostly is not now you need to adjust the gantry mirror again that the latest hit is exactly over the first one
10. after this two hits are perfectly on top off each other what can take a long time because you have to drive the gantry back and forth, then you drive the gantry to the upper most and farest from the gantry mirror and hit the laser again this should be again on top of the other hits what is again usually not now you have to adjust the gantry mnirror again till it hit the previous points after you acomplishe this you have to drive the gantry down on the same site and do the same you have to go back and forth a few times starting with the first position and work your way around this procedere can take a few hours from experience but you will need to do this aftyer a while working with the laser anyway because the alignement changes over time.
the first time it took me about 8 hours but after the third time it takes about 1 hour.
I hope this will help
greetings
walt



Hi hope everyone is having a good holiday season. My laser tube on my Epilog Mini 18 went out after about 6 months of minimal use.
Epilog sent me another 1 and its under warranty so I only had to pay customs/duty/whatever of about $300 US dollars to get it out of
customs. Putting the new tube in wasn't so difficult. But the alignment...wow....after a couple of nights on phone with tech support, and
many hours of adjusting hex screws...well they are on vacation until the new year I believe...pictures are worth 1000 words..what the &%$#
is going on now?? :confused::mad::eek::(:mad: This is on black aluminum, 600 dpi, 100 speed 40 power. Siiigh....so much varying degrees of engraving, lots
of erratic engraving...blurry.. I cleaned all the mirrors, tried many different focus heights etc....all look terrible. :confused: The bottom portions of the
"g" letters are terrible, the "r" letters are all blurred, and the lower part of the 8x12 inch aluminum is much lighter than the rest. Not to mention
the horrible picture. (600 dpi pic) 217192217193217194

heres the same pic on 3.5x2 inch aluminum....this is costing me $ in lost business. I have to tell people I'm "too busy" and can't do
their orders...217195

bruce edwards
12-26-2011, 7:05 AM
Hi thank you for that info.
I went through the alignment with Epilog tech. I just went through the alignment procedure again and red dot and burn mark is in the center at all 4 corners.

Glen Monaghan
12-26-2011, 9:43 AM
I think a significant clue is the fact that the top and bottom two lines show marked and sudden change in the "g" letters at the baseline, getting lighter where only the g's tails are being burned on the horizontal line, and getting better again when the curve is reached; likewise, the same area that is light on those lines is okay on the middle line, but there is similar light burning on the photo, starting at the text baseline of the third line and ending at the top of the fourth line. Again, I don't know what causes that, but it seems like the beam isn't getting up to power when there is little to burn on a given raster line. Power supply, tickle voltage, ???

Also, might the left-to-right and right-to-left passes be off a bit? Looks a bit like that on the second photo, at least on the left side, and that would make a blurry effect.

-Glen

Rangarajan Saravana kumar
12-26-2011, 10:26 AM
Hi,

Is the sheet engraved is flat on all the sides, from the photo, i guess a bend is there???

John Noell
12-26-2011, 1:44 PM
Hope you get it figured out. If it make you feel any better, I just replaced my tube and the Customs charges (duty + VAT) were more than that -- and then there was the $650 for FedEx, one-way. I still have to pay for sending the old one back or eat the $2000+ core charge.

The new one is supposed to be a 45 watt tube (despite the fact that they only put 30 & 40 watt tubes in the new Minis), but it does not have as much power as the original 45 watt tube did (and that one never matched the suggested power/speed settings for "40/45 watts" from the manual).

Martin Boekers
12-26-2011, 5:10 PM
When you have alignment perfect, put a bit od superglue on the nut than will keep it from
loosening with vibrations. You won't have to do alignments as often then.

Bruce Volden
12-26-2011, 5:39 PM
Bruce,

I guess one thing I would try - rotate the "g" 90 degrees (experimenting here) see what happens. My guess not much. From what I see from yer pics, perhaps the tube is not functioning properly. This first thing I would check is the output of the power supply that goes to the tube. My Epi TT needs 40VDC--from yer pics it appears all starts out fine and then kinda peters out after a bit of run time??? Maybe also check to make certain connections are tight for all areas of PS (power supply). If you have a meter, clip it on the PS and watch it while running a "test burn", making sure the voltage stays constant. Just something else to try anyway. Hope it helps.

Bruce

bruce edwards
12-26-2011, 11:58 PM
I looked at connections to power supply and look fine. Yes the metal is flat, I have 10+ other examples on various sized flat pieces..Here is something I just engraved. On the top left the lettering is almost perfect and clear...as it goes to the right and down it gets horribly blurry...I placed the photo and other lettering in the SAME SPOT as the clear big letters and the result is blurry and jagged. How can that be? I changed no settings, only moved the letters and replaced with the pic and letters. I sure HOPE its not the laser tube. Again. I must say I am a bit disappointed in this. For the cost I thought it would be trouble free for quite awhile. :mad::confused::(
217294217295217296

Rodne Gold
12-27-2011, 1:38 AM
Check your lens does not have a microcrack which manifests itself when the lens gets hot. Do you have a tickle voltage setting? Is it correct?
If alignment etc is spot on , it looks like the laser is not firing when and where it should, the picture has lines of firing way to the left of where it should be firing. A faulty tube would either stop firing or get weaker over time , this doesnt look like that. Have you checked the encoder strips if your machine has em?

Stephen Hooper
12-27-2011, 9:03 AM
This doesn't look like an alignment issue as the step-change is too great in the first set of photos. Couple this to the second set of photos which suggest a timing issue and I think you are looking at a tube issue or, more likely given that some of the firing seems early, an encoder/control issue.

If you have access to a clock gauge you can easily set this up at different points on the bed and check for encoder operation by checking step accuracy/repetition (leave the lid open so it doesn't fire. If this is not repeatable I would suggest cleaning the encoder first and retrying. If still not repeatable it could be a control or stepper-motor. If it is repeatable then I think you have a firing-control problem.

David Fairfield
12-27-2011, 12:05 PM
Pretty wierd.. What could go wrong with a tube, to cause the beam to scatter when the mirror/focus lens reaches the right side of its travel, then return to normal as it goes back to the left? I would think the position of the mirror/focus lens has no effect on laser beam quality, only how it focuses on the workpiece and when it fires. So I'm just wondering if it can be a focus issue. I don't know, but while Epilog Tech is off for vacation, I would go through the alignment process again, step by step, carefully following the instructions. Also check to see if something got bumped out of true, while you had the machine disassebled. My old vector grid started sagging in the middle after a lot of use, caused some focus issues, not this extreme, but it required replacement.

Ed Maloney
12-27-2011, 3:14 PM
Bruce - When Epilog walked you through the alignment procedure, did they start you off with aligning the red dot pointer first?

Ed

bruce edwards
12-27-2011, 11:43 PM
I cleaned the encoder strip, mirrors etc...Yes when Epilog walked me through alignment, the red dot pointer was 1st. :confused::mad: The machine is less than 1 year old with very light usage, so it shouldn't have all these problems should it? Maybe I got a lemon? I use it mostly for engraving dog tags and occasionally some wood. No cutting. No plastics. Very simple and light usage. Siiigh....This is a lot of down time on a new machine. :confused:

I noticed that when the beam is moving from left to right that it is mostly in a straight line...but also I can see it curve and dip at certain points.

Mike Ireland
12-28-2011, 11:23 AM
You might also try slowing down your speed to see if the quality improves. That should help the lower case 'g' and all letters that have similar descenders and ascenders.

David Fairfield
12-28-2011, 11:29 AM
I noticed that when the beam is moving from left to right that it is mostly in a straight line...but also I can see it curve and dip at certain points.

What beam? What is curving and dipping? Its not clear what you are describing, but it sounds like it could be the source of your problems. Nothing should curve or dip. The laser beam only travels in straight lines, it cannot curve, so I assume you refer to the motion of the focus lens? This should also only travel in a precise straight line with no vibration. If its not, then you have a problem.

Scott Shepherd
12-28-2011, 11:38 AM
Sounds like it's hanging up on something. I know I've read a number of threads where the air hose has snagged somewhere. You might want to check all those things and make sure nothing is catching.

Roger Leiva
12-29-2011, 11:05 AM
Bruce, and he solved the problem of your machine? I have experienced an equal and everything you can imagine. Back to normal situation should be a hang of it. 1-Check the leveling of your machine if it was moved to re-place the laser tube. 2-Experiment cut or engraved on each corner to check the table of engraving or cutting. 3-Clean the encoder strip and mirrors A and B, then C and have clean and lens. The first in the bottom left is encapsulated (only externally clean protective glass), so this should be left to remove the metal cover of the machine. 4-Use the laser (pointer) should fit the center of the lens, using the three available holes in the top of the machine, left side of the fans. 4-Once you do this, proceed with the adjustment of the approach, as recommended by the Technical Epilog, which probably arrived with the new laser tube. It should be a continuing operation.
Roger Leiva Costa Rica, P.Z.
Mini 18 Epilog 40 Watts -3 years