Agfa Xcalibur VLF80 - Vertical lag problem

[bmsouheib]

Hi everyone,

I have an Agfa Xcalibur VLF80 and I was working with Apogee RIP but recently I changed my RIP to Prinect working with printdrive.
At the beginning, everything was alright until I had this problem on my plates:

• The tiff file is engraved with a vertical lag of about 330mm (see attached picture) and sometimes (not always) the following error message appears on the screen "Linear motor controller Error".
  I cleaned the laser and everything was back to normal, the plates were well engraved but the next day I had the same problem and cleaning didn't solve anything.

Could anyone help me with this problem please ?

This is an example for a bad plate:

 

[ACT]

Agfa Xcalibur VLF80

Agfa Xcalibur VLF80

Hello bmsouheib,

I have worked with these equipments for a long time.
I am 95% sure the problem of Linear is not related to this issue.
Usually, Linear errors are related to dirty or damaged surface of linear encoder scale or misalignment of linear read head.
To diagnose the cause of this vertical lag I would ask you:
The image is just shift in vertical within the image frame or is it missing some part of the image.
1) if the image frame size is correct, so the problem can be the image generation (Prinect), the file transmission (Printdrive / PAC board) or the image processing (Pixel Format / Pelvis).
2) If it is missing part of the image in the plate, so the problem is related to vertical synchronism: Rotary board (verify the encoder disk / realign it), Rotary Servo (at electronic rack). Verify if the problem do not occur when you modify the exposition. Lower exposition (350) means High drum speed. Higher exposition (550) decreases drum speed. If changing the exposition fix the problem, so you just have to readjust the Rotary board.
I hope it helps you.
Good lucky

Antonio

Hi everyone,

I have an Agfa Xcalibur VLF80 and I was working with Apogee RIP but recently I changed my RIP to Prinect working with printdrive.
At the beginning, everything was alright until I had this problem on my plates:

• The tiff file is engraved with a vertical lag of about 330mm (see attached picture) and sometimes (not always) the following error message appears on the screen "Linear motor controller Error".
  I cleaned the laser and everything was back to normal, the plates were well engraved but the next day I had the same problem and cleaning didn't solve anything.

Could anyone help me with this problem please ?

This is an example for a bad plate:
View attachment 4827

 

[bmsouheib]

Hello Antonio,

First of all, thanks for your quick reply.
Here are some more information about the problem:

In short, we can summarize the problem in a shift of the starting point:
The machine often "thinks" that the position of the plate edge held by the drum grippers is 330mm away from its real position. The rest is of the job is performed consistently. Consequently, part of the image is lost.
What is bothering me is that it happens randomly, however the shift distance (330mm) is always the same.

 

[ACT]

Looking at the plate image you posted, I guess that the image window is correct. If it was just a error of the start of point (vertical) you would get a unexposed part in the top of the plate. It is not the case.
My main suspect is:
1) TIFF file was not correctly generated
Check hard disks integrity and perform disk optimization in RIP and Printdrive computers.
2) Image processing error at Xcalibur
Replace Pixel Formatter, Check/replace umbilical cables, replace Pelvis Board.
I can also imagine that the SDX board is not providing intermitently correct parameters.

By the way, check earth connection in your computer network and in engine.
Another commom problem is the temperature in the rack. If the fans are blocked, the temperature inside Electronic Rack increases and it can produce very strange effects. Open rack's door and keep an external fan blowing the boards just to be sure it is not the cause.

 

[bmsouheib]

Looking at the plate image you posted, I guess that the image window is correct. If it was just a error of the start of point (vertical) you would get a unexposed part in the top of the plate. It is not the case.
My main suspect is:
1) TIFF file was not correctly generated
Check hard disks integrity and perform disk optimization in RIP and Printdrive computers.
2) Image processing error at Xcalibur
Replace Pixel Formatter, Check/replace umbilical cables, replace Pelvis Board.
I can also imagine that the SDX board is not providing intermitently correct parameters.

By the way, check earth connection in your computer network and in engine.
Another commom problem is the temperature in the rack. If the fans are blocked, the temperature inside Electronic Rack increases and it can produce very strange effects. Open rack's door and keep an external fan blowing the boards just to be sure it is not the cause.

Dear Antonio,

Thank you very much for your concern but unfortunately my problem persists over and over. Even more, now I can't even have one single right plate and our production is blocked.

My new information is that the lag distance is not always the same, it varies with some millimeters from plate to plate.

I hope you will find me an answer since I am really desperate.

Souheib

 

[ACT]

Hello Souheib,
But you didn't inform what have you already done to fix it.
Have you replaced any board? Have you checked earth connections and rack ventilation?
Is there a trained technician/engineer working in this machine?
Kind regards,

Antonio

 

[bmsouheib]

Hello Antonio,
To resume, I cleaned my Xcalibur with air pression and the encoder with some alcohol but it didn't fix the problem but we realized that the frame is not missing any part so we took your first diagnosis:

1) if the image frame size is correct, so the problem can be the image generation (Prinect), the file transmission (Printdrive / PAC board) or the image processing (Pixel Format / Pelvis).

So, I brought back my Apogee 1.4, which I really hate, but it fixed the problem and now I have my right plates back.

Now, my problem is that I want to be independant from Apogee, I want to configure my Xcalibur with a printdrive to install Prinect on it or could you give me an advise if the recent versions of Apogee are good ?

Thank you very much

 

[ACT]

Good morning Souheib!
I am happy to see you identified the cause of your problem.
Now, I guess it is not so difficult to configure corrrectly Prinect and the hw/sw it is using (PC+network).
You should take special care about RAM memory/Hard disks configuration (use a good RAID system) and network speed. Also use a good defragmentation software in the RIP computer.
Apogee 8 is very good, despite it is expensive.
I have no idea about its costs comparing to Prinect. It also depends on the options you will use.
A lot of customers that sales its Agfa CTP keep Apogee to use as its workflow/RIP, even for other CTP brands.
Good luck,

Antonio