printing without the inking form rollers to the printing plate

[sitoprint]

Hi,
does anyone know whether there are any command on the classic qmdi
printing without the inking form rollers to the printing plate ?
Thanks in advance, regards.
Zarko

 

[Paul Cavanaugh]

There are none from an operators standpoint.

 

[rolandman]

although not from a DI background, am from a conventional offset background, but , how can you print without form rollers on the plate?

 

[2ampress]

Remove your form rollers...or at least back them away from making contact with the plate is the only way I can think of.

 

[Paul Cavanaugh]

Rolandman,

I noticed that also, but attributed the error to language differences. I believe they are wanting to use one of the units to pull powder.

 

[2ampress]

Pulling powder...

You can successfully accomplish this simply by feeding the job back through the press without impression.
I have done this on several occasions.
I have had some serious issues when attempting to fold a job because of the heavy powder required to keep the job from offsetting.
Another reason for doing so is also to remove powder from the job, but not for finishing, but simply for printing the second side. As you may have noticed or are aware...if you use heavy powder on the first side, when running it back through for the second side, powder will build up in certain areas on the blanket which result in lowered quality printing. Continued blanket washes correct the problem, but also uses more sheets to get back to quality printing. The build up of powder also breaks down the plate quickly which will result in your entire sheet toning due to ink adhering to the broken down plate areas.
Another option to remove powder would be to use compressed air and go through the job before printing.

Cheers,

Tracy

 

[Paul Cavanaugh]

On the powder subject...

Make sure you use a powder that it between 18 and 23 microns. These powders have less of a tendency to pit the plate and cause premature plate wear on the 2nd pass.

 

[rolandman]

Rolandman,

I noticed that also, but attributed the error to language differences. I believe they are wanting to use one of the units to pull powder.

ahh i see

usually on litho if we are dusting we wash the unit up and remove the plate so the form wont touch anything anyway, but of course you cant remove the plate from the di economacally

 

[sitoprint]

Thanks to all the answers.
The reason why I have asked this question is related to the washing of blankets. Blanket washup device we do not work properly (blanket stays wet after washing) and somewhere on the forum I read that someone suggested a solution to let a dozen blank paper through the machine (without the inking form rollers to the printing plate), and so removed the color from the blanket. It seems that there is no such options qmdi.
So I have to try once more to set up a system for cleaning blankets. I've already previously asked Can someone tell me which factory dimensions roller system for washing (blanket washup device). I doubt that my rollers under the action because I bought a second hand machine and I do not know whether it is a brusio.
Best regards

 

[2ampress]

You may want to go with a wash with quicker evaporation, that could solve your problem...Ask your supplier what other wash is available.

Cheers,

Tracy

 

[Paul Cavanaugh]

The only blanket wash Heidelberg ever recommended and the only one I ever saw work reliably was Pronto. If anyone else knows of another that works as well, by all means post it.

 

[2ampress]

I switched to Color Lok Network Wash, as it was about $50 cheaper per 5 gal can and seem to have about the same characteristics as Pronto...Now on the Ryobi DI, we are using the same blanket wash as the other pressmen are using on the 3 different 40" Man-Roland presses are and seems to work just fine...not sure of the manufacturer, but will post on Monday when I get back to work.

Cheers,

Tracy

 

[mutti8000]

Deinking of the blankets

Hi

There is in fact a software/rom upgrade that enables you to do de inking of the blankets.

When the machine is running in production mode just press the blanket wash once, and the blankets de-ink onto paper. Cost a little bit of paper, but greatly reduces the maintenance on the blanket wash system!

Maybe Paul can can shed some light on which sofware version/rom upgrade is needed?

/Morten

 

[mrheidelberg]

Try Pronto Plus from Varn.

It is only the DI Pro that can automatically strip ink off the blanket prior to a blanket wash if required.

 

[mutti8000]

Hi Mr. Heidelberg

Sorry, but that's not correct.
It's working on my 1998 QMDI-plus. (i don't know about the classic)

My paperwork says from Software version CPT2 DI 05.20 ZTK

 

[FFR428]

You may want to go with a wash with quicker evaporation, that could solve your problem...Ask your supplier what other wash is available.

Cheers,

Tracy

I agree. You can also try to add more idle cycle time to air dry after they are washed. The Ryobi DI I ran had the same problem. Even then I would still need to hand wipe the edges. Also some stocks and powders left a heavy residue sometimes and I'd have to hand clean them. With the correct solvent and dry time it should be pretty good though most of the time.

 

[jan]

Hi Sitoprint,
in fact there is a possibility to remove the ink from the blanket using waste paper.
You need an upgrade of the press software. It is a Eprom chip that you have to replace .
It used to cost about 120€. Ask your Heidelberg representative , or send me PM so I will ask HD the current price and send you quotation. In this case inking rollers are not active by the program, they are also not active using standard washing program.
Solvent on your blanket after washing is due to the bad adjustment and/or maintenance of your devices.
The rollers should have 49,6 x 348 mm, material 909, shore A35.
rgds
PS. does brusio means abrasion for you?
Jan

 

[mrheidelberg]

Hi Mr. Heidelberg

Sorry, but that's not correct.
It's working on my 1998 QMDI-plus. (i don't know about the classic)

My paperwork says from Software version CPT2 DI 05.20 ZTK

Sorry......i should of mentioned it was software related and that software is one of the later versions.

 

[Paul Cavanaugh]

In 2005 there was an upgrade you could purchase for your Classic and Plus machines to give you the option to run sheets through the press to help dry the excess blanket wash solution off. The EPROM Software version is 5.20 and the part number to order it by is 00.785.0884/02.

There were a couple of requirements before this could be added to your machine, they are as follows:

The press must be equipped with software version
1. DI 02.41 (DI 46-4 Classic) or DI 03.41 (DI 46-4 Plus).
2. The sensor 11B3 ”Feeder pile in control range” must be installed. This sensor is standard equipment as of press serial number 990 822. If the sensor 11B3 is not installed, you must have it retrofitted by a service technician.

The following explains how to use the Blanket wash "deinking" function:

The function ”Blanket deinking” greatly reduces the frequency of maintenance and cleaning of the blanket
washup device. When the press is on impression, you can activate the ”Blanket deinking” function by pressing the button Wash blanket.The inking form rollers and the ink vibrators are thrown off. The inking unit remains inked-up and the blanket is deinked via the sheets.

Procedure
The press is on impression. The LED in the button Wash blanket is on.
1. Press the button Wash blanket. The inking form rollers and the ink vibrators are thrown off. The LED in the button Wash blanket goes out. Pressing the button Wash blanket a second time will not trigger any function.
2. Wait until very little ink remains on the sheets. Press the Production button. The press goes off impression.

One of the other very help items about this software is the fact it also helps to reliability of the feeder by decreasing the distance increments the feeder pile raises each time. If any of you are familiar with the "deep" errors when running high speed and thick stocks this software resolves those issues.

 

[Marc Bremer]

"One of the other very help items about this software is the fact it also helps to reliability of the feeder by decreasing the distance increments the feeder pile raises each time. If any of you are familiar with the "deep" errors when running high speed and thick stocks this software resolves those issues."

Could this also resolve my problem described in the post running large envelopes (Marc Bremer). The pile doesn't rise enough after feeding an envelop so after 40-50 envelopes the pile is to low.

Thanks