Cracked Labels

[Aussie0zborn]

It’s too cold. Soften it up a bit and see how you go.

[llary]

Your puck is too cold, what PVC supplier are you using?

Do you have any idea what the gearbox ratio is on your machine because motor rpm is not a very helpful indicator? We really need to know the actual screw rpm.

What happens if you use unprinted white labels? Are the printed labels offset printed or are you using some kind of digital printing?

[Aussie0zborn]

Heat it up a little more until you can, or at least get close to leaving a fingerprint. Don’t burn the compound in the process.

[mich]

still on this subject of labels: has anyone ever encountered the following problem: the glue of the labels smears to the side and the stamper gets a stain like this.

Manual or automatic press? If manual are you leaving hot pucks sitting around before pressing?

Never, we extrude only one puck per record.

We have other different stains sometimes:

Those cracked labels are definitely a stamper issue as Misjah suggested, that label part needs to be sanded and a good stamper service must provide them sanded and ready to press.

That puck seems "cold", I don't know how many heaters your extruder has, but I'd suggest rising that temperature to 140º and try, it doesn't seem very compact either but I'm not an expert in Newbilt.

For those pictures, first looks like dust on stamper, second looks like some liquid (oil?) on stamper, definitely not glue, but those second liquid marks must be seen in the stamper after pressing, or also could be a compound issue.

Best!

Eugenio

[Vella]

Hey Filipe
I have had this problem before with different colours and pvc compounds, as well as other haze problems.
I am using a duplex system from Newbilt, same extruder as you are. The ones you showed on the pictures go off with a stamper cleanning. I tend to belive is gassing from the pvc while pressing, not related to labels at all. But I also don't discard humidity as one possible problem, either inside the cake or a the presses. Those are my best guesses. How often this happens?