dampening issues sm52

Good morning all,
I am having issues setting the dampening system for short width jobs on this press. when setting the water pan roller the chrome the book implies that the crowned roller should be tightened until the bands disappear from ends of rollers. These are new rollers and these bands never disappear no matter how tight I make the setting. Never did with the old rollers either but did not have these issues. Setting the form to the chrome is also an issue with what is the real setting and what is a gost setting from rollback when disengaging???
I run full length sheets no problem. Even 11 or 12 sheets not to much problem. Smaller sheets or envelopes are problematic. Water tends to build up on ends and work its way in toward center.
Sugestions please...

 

Have you pulled out your roller and verified that it was ground with a crown? Ive never ran a SM 52 so im not sure if they even came from the factory with a crown as I would think it would not be needed. Perhaps someone could verify this???

 

Thanks, I could be incorrect but I believe the crown is 10 or 12 thousands. I know they are crowned because when setting the center definitely dries before the ends.

 

Dear Sir,
Press at the over-dampening button, then.
Adjust the water Pan roller to the metering roller, open the screws counter clockwise until the water appears at your pan roller, then begin to turn clockwise side by side while pressing the over-dampening button until the roller become dry from the middle, then continue squeezing until all the roller surface dries completely except 10mm at both edges, you can squeeze 1/4 more turn.
Switch Off your fridge.
Move out the metering roller.
Adjust your dampening form roller to the dampening distributor 4.5mm Ink strip.
Adjust the intermediate roller to the dampening form roller 2.5mm.
Install the metering roller, clean and dry it well.
Adjust the metering roller to the dampening form roller 5mm, you can check the ink strip at the plate simultaneously 4mm.
Check the adjustment of the water Pan roller to the metering roller again.
Note: If the water pan roller OS is not drying well, you have to check your roller journal, and replace it.
Send me again your feedback, then we can continue solving the issue.

 

Thank you so much, I'll give it a try next week. By the way, I run normally 10%-12% alcohol . also do you use ph strips or a conductivity meter?

 

If you have an air curtain on this press open blowers on ends when you run small sheets.might help

 

Thanks Jack, my press is not blessed with that accessory.

 

You are welcome,
I prefer to use Saphira fountain solution with 2.5%.
Note: don't try to reduce the PH by adding more fountain solution since this will not be the right way. Just add the recommend percentage by the manufacturer.
IPA 7-9%.
Empty your fridge, then mix up water, fountain solution and IPA, then measure the conductivity and write down the number and keep it. Print as usual for 2-3 weeks. Measure your conductivity again, compare the new and the old number.
When the new number is 1000 over the old number, then you must change the water again.
Check also your total hardness of the tap water, should be 8-12 dh (according to german standard).
Good luck.

 

WOW.... Thats alot of alcohol!!! I do know that on the 102cm Speedmasters most companies that recover rollers will offer different crown depending on how much alcohol you are running. Just keep that in mind when it comes to recovering your pan roller. If your having dampening problems with 10 to 12% alcohol I would say that something is very wrong with either your settings, your fountain solution, or other consumables!!!

 

As mentioned an air curtain will greatly improve your dampening control when running smaller sheets across the cylinders. I would not consider it a major feat of engineering, nor a major expense, to fab up your own air curtain system. A small blower, some plumbing, hoses, valves, and a switch would be all thats required. I was able to build one on an old 2 color Roland many years ago and get it all up and running perfectly within a single working day. May not have been as pretty but worked as well as anything out of the Heidelberg factory.

 

Hi friends
Asem alsafady give the correct answer for the dampenning solution parameters
I would add just some information the conductivity must be between 1200-2500 you can use an osmosis system to regulate the starting conductivity I recommend that you start with a conductivity of around 1000 micro simens added 4% of additive it will give 1400 micro simens and then added 8% alcohol it will give 1200 micro simens to have more information on the mixture and the dampening solution do not hesitate to contact me we provide power point training on this , ph between 4.8-5.5 , hardness of the tap water 8 dh , temperature of solution between 9-10
We peovide also training about all printing problem causes and solutions be welcome .
Good luck

 

yes Turbotom,I agree. Unfortunately its where it seems to run best. Problem is we put a new set of rollers in and changed plates to Kodak self developing on press at the same time. Nothing has been the same since. I believe the grain of discontinued Kodak plate was deeper than new plate, new cannot carry as much water without flooding. But what do I know. I have to get Kodak involved!
The developing background non image is supposed to develope off on sheets as they pass through but developed out almost before sheets pass through meaning the removed background IS traveling to ink system and therefore water system.....you could be correct turbo thanks

 

Have you tried wiping down the new plates with water on a sponge BEFORE you try rolling them up? If you opt to try that you will need to begin doing it that way only AFTER youve done a complete flushing of the dampening systems tanks, sump, and lines. Ive found that rolling them type of plates up when new tends to contaminate the system, and only gets worse as you go from form to form.

 

Are these Kodak Sonora process-less plates? If so the plate emulsion comes off when rolling up (the ink is what removes the emulsion, so just hit production and go), it goes into the ink system and then back down onto the blanket and comes off on the first 10-20 sheets. That’s how they’re designed to work and on certain segregated presses it’s great….

I don’t know but the problem may be that the Alcolor dampening system integration added into that scenario could be bringing you different results with these types of plates. Maybe you could try segregating your Z roller for awhile and see what happens?

On a different note: What I always did with Alcolors was tightened the meters 1/2 to 1 full turn just past heavy water, so it disappears all the way across the roller. Then at the end of every shift I loosened them 1 1/2 turns before cleaning them. Then at start up every day I tightened them 1 1/2 turns to keep it simple and consistent.

I wish you good luck with your situation!