Plates are randomly to short or too long...

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Plates are randomly to short or too long...

Postby MrPlateMaker » Mon Jun 07, 2021 10:37 am

So Recently some of our plates have been coming back out of register (to short or too long) we use crosshairs as our reference points, most of the time our mounters are catching this issue but sometimes it makes it out to press before we notice it..
Plates are Asahi .067 DSH 50x80 burned on a Esko CDI Advance 5080, nothing has changed on any of the machines everything else about the plates are perfect except the random (too long to short) im thinking its a dryer issue and its randomly getting hot and over drying certain parts of the sheet...
i checked with a temperature gun and everything seems okay while i am standing there reading with the probe the wire isn't long enough to get all the way to the back of the dryer though....

its just really bothering us because sometimes it will just be 1 of the plates off of the full sheet thats not right and the next time it will be 2-3 of the plates that aren't right, i cannot replicate the issue if i tried.

we know this is not a pressside issue because out mounters catch the issue most of the time..

has anybody ever seen random shrinking issues, is it typically the dryers?? any help will be appreciated.

Thanks a bunch..
MrPlateMaker
 
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Re: Plates are randomly to short or too long...

Postby Frank Burgos » Mon Jun 07, 2021 10:46 am

You don't say whether you measure the plates to confirm they don't measure the same, but on the off-chance that it's not the plates, here are a couple of mechanical conditions, at mounting, that have result in something like what you describe:

Differences in bare-cylinder/sleeve diameters
Differences in mounting tape
A combination of these

If you haven't confirmed by measuring, I would. If they measure correctly, I'd measure the cylinder/sleeve diameters, precisely, and test with only one type of tape off the same roll.
Frank Burgos
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Re: Plates are randomly to short or too long...

Postby MrPlateMaker » Mon Jun 07, 2021 11:23 am

sorry i wasn't clear enough,
our mounters have the ability to check the length of our crosshairs without fully mounting the plate on a cylinder, so they can essentially measure them and see that they are short/long...(some mounters have been taking this extra step since we have been having this issue, to save us time and money before the plates get mounted and on the press)

My Manager and Myself have essentially narrowed it down to the CDI or the Dryers, I am under the impression if it was the CDI we would be seeing it a lot more often so i think its a dryer issue..
MrPlateMaker
 
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Re: Plates are randomly to short or too long...

Postby Frank Burgos » Mon Jun 07, 2021 11:40 am

Thanks for the clarification. Looking forward to other responses
Frank Burgos
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