Question: Didde Start-up Procedures

[Sound Design]

Howdy Folks,

I'm a prepress guy at a printing company and they are running Didde 175's / 860's downstairs. The presses have conventional dampening systems on them.

My question is what is the proper start-up procedure? Should the operators be dampening their plates before dropping the form rollers etc.?

I used to run sheet fed presses years ago and always dampened the plate before dropping the form rollers to prevent ink build-up, screens being filled in and to save on paper and so on.

Thanks, Bob

 

[HPC]

Your 860s should have either quad flow or tri flow, the 175s had conventional. Anyway, the best way to start up a dry web is to have a very small sponge in the tray, start the press on a slow idle, while the doctor is spinning add fountain solution to it only with the fountain water on. Drop your water form, look for a shiny plate, then hit ink and impression. Shine is good, dull is bad.

 

[Sound Design]

Your 860s should have either quad flow or tri flow, the 175s had conventional. Anyway, the best way to start up a dry web is to have a very small sponge in the tray, start the press on a slow idle, while the doctor is spinning add fountain solution to it only with the fountain water on. Drop your water form, look for a shiny plate, then hit ink and impression. Shine is good, dull is bad.

Thanks for the reply. The way they are doing it now . . . looks like their just dropping the form rollers on the plate dry after start up and relying on the rollers/fountain to clean the plate. It makes more sense to me to dampen the plate first like you are stating.

 

[HPC]

Thanks for the reply. The way they are doing it now . . . looks like their just dropping the form rollers on the plate dry after start up and relying on the rollers/fountain to clean the plate. It makes more sense to me to dampen the plate first like you are stating.

On a press with conventional its much easier to get it balanced once the ductor is saturated. On a press with quad flow, tri flow or Dahlgren the ink/water is combined, but dampening happens immediately.

 

[Sound Design]

On a press with conventional its much easier to get it balanced once the ductor is saturated. On a press with quad flow, tri flow or Dahlgren the ink/water is combined, but dampening happens immediately.

So a quad flow, tri flow or Dahlgren doesn't require any manual dampening? Only with the conventional system.

 

[HPC]

Correct.

 

[Sound Design]

Correct.

Thanks again for the info. This will help a lot.

Bob

 

[CARLOS73]

Thanks for the reply. The way they are doing it now . . . looks like their just dropping the form rollers on the plate dry after start up and relying on the rollers/fountain to clean the plate. It makes more sense to me to dampen the plate first like you are stating.

Thats what i do... Forms first, wait a few seconds then blankets.

 

[CARLOS73]

I need some pointers on setting meter roller and chrome roller. Didde 860 quad flow.
First i check my stripes then meter and chrome.

But i just can't seem to getting it. It takes me a long time to figure it out . But next time it will be a different solution. So frustrated.

Any tips will be greatly appreciated.

 

[ChadwickHE77]

Carlos did you get this figured out? Do you have a press manual? We have a couple quad flows in our shop and there is a process to follow to set them up. Let me know and I can post it.

 

[CARLOS73]

Chad... I've been getting better at setting pan,meter, chrome rollers.

But I would still like to hear how others do it.