Flexo Plate Quality

[prepress@labels]

Does anyone have ideas for verifying the quality of a flexo plate?

Specifically, I'm talking about plates which have been used and stored and are now being re-used. Quality problems are usually found while on press for these previously used plates, meaning that if there's a quality problem my prepress department is rushing to create new plates while the press sits idle or production moves on to another job.

I've seen some equipment in the $10,000 range from X-Rite and others that are designed to check dots/exposure, etc. That's not what I'm looking for. Instead, I'm looking for a way to identify typical problems with old or used plates. Example: 2 or 3 % dots that have been degraded, small type that gets broken up, etc. My understanding is that these problems are caused by multiple press runs and general wear and tear. (We use Cyrel plates from DuPont.)

I come from the offset print world and this type of problem is new to me. Any help is greatly appreciated.

 

[tmiller_iluvprinting]

Is there any way to proof the plates before the pressrun? If this is a frequently occurring issue,
would remaking and remounting the plates on repeat work cost less than press downtime?
Best regards,
Todd

 

[meddington]

I've seen some equipment in the $10,000 range from X-Rite and others that are designed to check dots/exposure, etc. That's not what I'm looking for. Instead, I'm looking for a way to identify typical problems with old or used plates. Example: 2 or 3 % dots that have been degraded, small type that gets broken up, etc.

Why wouldn't this be what your looking for (besides price)? A device that analyzes dots should certainly be able to assist in identifying degradation.

 

[prepress@labels]

Proofing the plates is exactly what I'm looking for, I was hoping someone had a tried and true method. At this point I'm looking to find some sort of application tool (a very fine paint roller?) to test plates quickly and easily before getting to press. My other thought is a camera of some sort that can zoom way in and give us a very high-res image to look at prior to mounting.

The problem is not so frequent that remaking plates is a cost-effective option.

The X-Rite solution works great for measuring dots, but a tiny portion of a serif missing from a 4 point Times Roman font won't be flagged by this method.

Thank you for your replies, even if they don't specifically have the answer I'm looking for they often get me thinking differently and help to point me in the right direction.

 

[meddington]

My other thought is a camera of some sort that can zoom way in and give us a very high-res image to look at prior to mounting.

This is essentially what these flexo plate readers are in most cases. Should be able to allow for visual check or type serifs, if you could position the ccd over it.

 

[Grnofslt]

We use both flexo mats and offset plates where I work. We do not print full color tight registration, high line screen type flexo. We make custom file folders that have forms on them. But we do have a procedure for sending mats to the floor. First off, our flexo operators are required to fill out a form that goes into the mat jacket that tells us if the operator thinks the plate is good, or if there are problems with it, he lets us know on this form. Also the operator is required to put what we call the Last piece sample, that is, this is supposed to be the last piece from the job just run into the mat jacket. When the customer reorders their job we look at this form and the last piece, we also inspect the mats through a magnifying glass, or this binocular magnifier that I have under a bright light. Here we look for mats that have been scrubbed by the machine hitting too hard at times, broken type, cracked stroke lines in the forms, type and areas that have been rounded through years of wear. If one of us finds a mat that is questionable we bring it to the attention of our print team manager who makes the call to order a new mat or to send it to the floor. It isn't perfect, but that is the procedure we use.