Laminator not pushing down hard enough? Black ink looks grey....fingerprints

[MarkH42]

We have a GBC Professional 1064WF Cold Press Laminator. We have the calibration tool and we periodically adjust the pressure on one side or the other so that the pressure is equal. But recently it seems like the rollers aren't pushing down hard enough. I have attached a picture of a section of black ink on a 3mm ACM sign we printed on our HP550 flatbed printer and just laminated. When we laminated it, we ran the sign through our laminator on its tightest setting (fully closed - last notch - see second pic below) and the black ink appears dark grey. When our operator was wrapping the edges and trimming the excess laminate, his fingerprints are what is appearing in the picture. Wherever you press down hard, it gets darker - closer to black. The angle of the picture really makes it look bad, but when you first look at the sign, it looks fine. You don't notice a problem until you touch it. The lines you see are a reflection of the roof tiles, by the way. The fingerprints are the problem.

My first question is, should we be running it on the tightest setting when we are adding laminate to a 3mm sign? Our production guy says yes, but I'm not so sure.

Second question is, if we take off the end covers and tighten the pressure on both sides, is that going to resolve the issue? I'm hopeful it will, but I want to be SURE I'm not overlooking something obvious that could be causing this problem. I appreciate any input you may have.

 

[unclebun]

That's called silvering, and with time and warmth it will go away. If you don't normally experience it, it's probably because it's cold now. The adhesive of the laminate can't flow because it's too cold.

 

[MarkH42]

That's called silvering, and with time and warmth it will go away. If you don't normally experience it, it's probably because it's cold now. The adhesive of the laminate can't flow because it's too cold.

Interesting.... It is definitely cold here for us (mid 20's last night) and I had not considered that possibility. It is 65 or so in our production area but the thermostat was set to 60 last night and this was done pretty early in the morning. So if we hit the sign with a heat gun, it should help? I forgot to add that we are using an Arlon cast wrap laminate. We normally use a callendered laminate but we ran out and were in a rush to complete this job. How do we combat this in the future?

 

[unclebun]

I wouldn't use a heat gun. Too much risk of overheating when you try to cover a large area like that. Just a hair dryer would do. We don't usually worry about the minimal amount of silvering we get with our GBC laminator, but we try to keep our work area around 65-70 degrees in the winter.

More pressure can help, but on a GBC laminator you're really not setting pressure, but thickness. If you set it too thin the ACM won't go through.

 

[WYLDGFI]

Try putting another sheet beneath it and see what happens.....part of the issue is heat? Or lack thereof....and it's not allowing the adhesive to flow decently.

 

[iPrintStuff]

Slivering is pretty common with UV, we run a heat assist laminator and if you slow down the speed and put the heat at around 40 Celsius it goes away completely.

usually particularly noticeable with Matt laminate.

 

[greysquirrel]

have to go heat assist...do yourself a favor and dump that laminator when you can...having the ability to dial in your nip settings accurately along with heat assisted rollers will solve your issues

 

[SignMeUpGraphics]

Orafol 215DU is specifically made for UV prints with a thicker layer of adhesive to sink into the texture of the prints and is supposed to minimise this issue.
We haven't had the need to try it yet, but saw it a few years back at a trade expo.