Lost first 1/4" of X

[Robert Walters]

I received my replacement laser cartridge yesterday and was engraving anodized aluminum and the first 1/4" of the x axis engraving was "shadowed".

I inserted a 1.50" spacer and shifted everything over and engraved fine.

I really don't want to "give up" that 1/4" as I align everything to the rulers plus there is a 2" indent where the ruler goes from 1/8" to a 1/16" thick for the auto-focus which works great on my machine and I don't have any 1/16" spacers I could use on a regular basis.

Any suggestions?




Sidenote...
NEVER EVER test a new laser tube using manufactured wood products.
We tried forever to cut 1/8" particle board (just scrap I had on hand), even at 100% pwr, 0.2% speed, 1000 PPI, and it still would never cut in a single pass. Tossed in 1/4" solid wood, and no problem at all! *ARGH* I think I scared the rep when I started ripping apart the particle board with my bare hands and throwing it in the trash, lol.

[Brian R Cain]

Can you post a photo of the shadowing? When you say the first 1/4", do you mean 1/4" from the ruler or the first 1/4" of engraving, bearing in mind this might be some way further in.

Try running the machine in single direction mode to see if you find the same thing. In the driver, press Shift, Ctrl and 8 together. This brings up a window that allows you to set this. Choose East to West then repeat using West to East and post what you find.

[Robert Walters]

No pic available right now....

It's like a gradient going from left to right, darker to lighter.

Where lighter is the proper power level,
and darker is like the power is 50% lower than it should be.

1/4" from the edge of the ruler.

If I shift everything (artwork/material) to the right by 1.5" using a spacer, everything is fine.

[Dan Hintz]

Sounds like a typical problem (moreso with ULS machines as they don't offer the ability to tweak per material, ala Trotec)... as the head slows down, the laser power is reduced in an attempt to even out the power density over time. It's a linear regression, which will almost never work perfectly (and often nowhere even close to perfect).

[Brian R Cain]

Sounds like a typical problem (moreso with ULS machines as they don't offer the ability to tweak per material, ala Trotec)... as the head slows down, the laser power is reduced in an attempt to even out the power density over time. It's a linear regression, which will almost never work perfectly (and often nowhere even close to perfect).

Wouldn't that have the same effect in any part of the bed? I'm wondering if the drop off in power is due to an beam alignment issue. Have you checked the alignment, Robert? If I remember correctly, you mentioned you bought this machine second hand. Although replacement tubes are sent out pre-aligned and generally pretty good, we don't know whether the original was tampered with at some stage. If that was the case, it's possible that as the carriage moves right into in the near field, the beam is hitting the air assist cone.

If this turns out to be the case, after you've adjusted the #2 mirror, you may need to re-align the cone as well. The bracket it's mounted on is held in place by two screws under the carriage. Slacken these off and move the bracket around until you see the red dot pointer cleanly.

[Scott Shepherd]

Wouldn't that have the same effect in any part of the bed?

Sadly, no. It only impacts the far left and right sides of the table. That was Trotec's sales pitch years ago. Their trade show demos featured a piece the length of the table and it would engrave at 100% speed from end to end. Something no one else could do without having the edges fade out. I don't recall it being an issue on the M series, but it's been a while since I've seen one of those. I thought the M series ran a bit slower than the PLS and VLS, so the fading out on the edges wasn't an issue like it is on those machine, but I could be wrong.

It certainly could be the alignment.

[Kev Williams]

Does the ULS driver in this particular machine have a "wood" setting? My ULS driver doesn't, but my LS900 driver does, and it further reduces the edge power to prevent the wood from overburning at the ends. I've had dark ends when doing anodized with the wood setting turned on.

[Brian R Cain]

I don't recall it being an issue on the M series, but it's been a while since I've seen one of those. I thought the M series ran a bit slower than the PLS and VLS, so the fading out on the edges wasn't an issue like it is on those machine, but I could be wrong.

The speed depended on the specific models. The M-300, V-400 and X-600 ran at 40 IPS. When they introduced the M-360, V-460 and X-660 the speed increased to 75 IPS which is the same for the PLS series. The VLS runs at 50 IPS.

[Brian R Cain]

Does the ULS driver in this particular machine have a "wood" setting? My ULS driver doesn't, but my LS900 driver does, and it further reduces the edge power to prevent the wood from overburning at the ends. I've had dark ends when doing anodized with the wood setting turned on.

The driver for the M-300 will be similar to yours, Kev. Using the image enhancement feature helps but to do so, you need to run some tests first with each material you use to find the minimum power required to get clean engraving at maximum speed, then make adjustments to the Density and Contrast settings. It's all explained in the manual which you can access in the driver by clicking on the ? icon, which from memory is located at the top right of the driver. You only need to do the testing once then save the settings for each material.

[Robert Walters]

The alignment is off in the factory tube, so I'm going through the process of compensating for that and realigning the mirror. *SO* close, about 0.5mm left to go between all four corners.

I realize that I probably don't need to be that accurate, but it's not like I will be realigning all the time, and I'd like to know that the laser is hitting evenly and consistantly across the whole table.

Once I get the realignment finished, I'll recheck for the 1/4" loss.

I'm a wee bit annoyed the $1200 replacement tube is off like this though,
I can see it's off center from the portal hole by at least 1/8".


SHIFT+CTRL+8 does nothing in my driver on any screen.

Not sure about a WOOD, but do have a rubber stamp setting.

I never had this issue before the replacement tube, so maybe it could be the alignment.

[Brian R Cain]

"SHIFT+CTRL+8 does nothing in my driver on any screen."

Just had a look. Go to the advanced tab and press Shift+Alt+8. Sorry about that.

[Robert Walters]

First off...
The beam coming out of the replacement laser cartridge was off center by (what I would consider) quite a bit.

I spent a few hours compensating for this by readjusting the mirror alignment. I am close on all four corners.


Second...

I'm not sure what to think now, I'm seeing additional artifacts of various kinds coming out of the woodwork:

In the photos that follow, the left edge of the 3/4" MDF is sitting flush against the machine's left ruler.

Each "section" engraved is 3" long; the first two are 1" tall, the next three are 1/2" tall.

The first 1/4" of each engraving is crap.

In the "RIGHT TO LEFT", the left edge of the "E" is missing parts.

L2R and R2L both have "meteor tails" equiv to the direction of travel of raster engraving.

BIDIRECTIONAL has a tail on it's left side.

I believe (hope) the vertical banding seen in all of them is the MDF itself.



I NEVER had any of these issues with my previous tube.
From what I've read, I would kinda expect this from a chinese machine, not a $1200 tube.


1. Overall view:
IMG_20140621_210846.jpg


2. I couldn't pick this up in the like I wanted to, but those two dark bands have a significant height difference that you can easily feel.
IMG_20140621_175059.jpg

3. Same settings as #2, just shifted the artwork over 1/4".
IMG_20140621_210901.jpg

4. comet streak on right side of "RIGHT"
IMG_20140621_210816.jpg

5. comet streak on left side if "RIGHT" and on left side of "BIDIRECTIONAL",
The "T" and "O" have a pixel shifted over to the left; misfire?
Still have that strangeness on the first 1/4" from the left edge:
IMG_20140621_210755.jpg

6. More comet streaks on the right side of all three shapes:
IMG_20140622_011509.jpg

7. Mid portion of circle is shifted left, not sure what's up with that.
IMG_20140622_011535.jpg



Brian,

Not exactly sure why you asked for the L2R/R2L, but there ya go

[Scott Shepherd]

I can't help you with the issue, but I will say that you can have issues with a factory tube. Years ago, they came out with a new driver. When they did, it changed something that affected parts I ran weekly at the time. I called and they told me it was no way the driver. So they started sending me parts. Nothing fixed it and no one would listen that it was a driver related issue. They sent me a new tube. I tried to align it and I couldn't get it aligned. It was way off. I was told basically that I didn't know what I was doing. After many failed attempts to align it, it wouldn't align. They sent another tube. Same thing. After a day or two, they shipped me a new tube and told me that they went back and checked the alignment fixture and someone had moved something critical and all the beams aligned on it recently were off. They sent a new tube out, it lined up instantly and there was no issue.

It didn't solve my problem with the driver, then after replacing just about every part in the machine, a tech was in the area and came by. He watched it run for about 30 seconds and said "that's a driver issue". He went back, put me in contact with the programmer, and I had a fix the next day.

My longwinded point is that just because it's new doesn't mean it's right. It kind of looks like a tickle setting to me, but I'd certainly send those photos to ULS and get their input.

[Robert Walters]

I'd certainly send those photos to ULS and get their input.

Some were sent to the local Rep AND to ULS after posting here.


I'm fully aware that NEW != GOOD (been there, done that).
At $1200, I expect perfect alignment at the very least.


Your driver issue...
That's the one thing I love about VMs ESPECIALLY on Windows,
Before making changes, take a PRE-INSTALL/UPDATE snapshot.
Make your changes.
Take a POST-INSTALL/UPDATE snapshot.
Try things out.
Then you can revert back and fourth as you please.


There is a tickle setting on the control panel and DIP Switches in the laser cartridge.
I'm told the control panel setting are insignificant and it's the DIP switches that matter, they also happen to be behind a "WARRANTY VOID IF REMOVED" sticker.


There is also a TUNING slider, but I have no clue what it does.
The docs I've come across don't go into any real detail.

I'm still reading the OEM docs, as it gives more non-proprietary technical details than the normal docs.

[Dan Hintz]

Get a replacement tube and be done with it. They sent you a bum one (likely someone mistakenly pushed it past the optics alignment step without verifying it).