Cracked Labels

[jlbfalcao]

Has anyone ever had a problem like this. We left the labels at 140 degrees for about 2h and tested with different labels.

CleanShot 2022-08-11 at 09.26.46@2x.png

[misjah]

stamper sanded well enough under label?

[untitledthe]

Try for longer time in the oven

[jlbfalcao]

stamper sanded well enough under label?

We never tried it before, but it worked! Thanks.

But I have some questions:

1) What's the best way to do that without screwing up the stamper?
2) When (and why) is this process required for some stampers?

I appreciate any help you can provide.

[misjah]

stamper sanded well enough under label?

We never tried it before, but it worked! Thanks.

But I have some questions:

1) What's the best way to do that without screwing up the stamper?
2) When (and why) is this process required for some stampers?

I appreciate any help you can provide.

It’s not done on the stamper its normally done on the lacquer/dmm before making the stamper.

[Aussie0zborn]

The label area on the master disc (either lacquer or DMM) needs to be roughened so that label has something to adhere to and not crack. Also, the PVC needs to be hot enough/soft enough to prevent cracking of labels. Pressing speed also plays a role.

Drying is only to remove moisture from the paper - its not to prevent cracking so don't follow the advice above and bake them longer. (This would increase the chance of labels cracking).

[filiperibeiro]

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.

[Aussie0zborn]

Labels don’t use glue. The heat and pressure allows the labels to adhere to the record. This is something else.

[llary]

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?

[llary]

Try for longer time in the oven

That will make the problem worse. Need to throw those baked labels out and start again baking very carefully checking every 15 mins

[llary]

stamper sanded well enough under label?

We never tried it before, but it worked! Thanks.

But I have some questions:

1) What's the best way to do that without screwing up the stamper?
2) When (and why) is this process required for some stampers?

I appreciate any help you can provide.

It’s not done on the stamper its normally done on the lacquer/dmm before making the stamper.

It's no problem to sand directly on the label area of a stamper, we use 100mm sanding discs and a turntable to do this more efficiently

[llary]

2) When (and why) is this process required for some stampers?

I appreciate any help you can provide.

Sanding the label area is done to reduce the contact surface area between mould and stamper so there is less heat transferred to the label.

The opposite is true for the back of the groove area which needs a high polish for excellent contact and efficient heat transfer.

[filiperibeiro]

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:

[misjah]

It's no problem to sand directly on the label area of a stamper, we use 100mm sanding discs and a turntable to do this more efficiently

Sure you can but there’s a reason it’s usually done on lacquer/dmm.

[Ketaman]

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.

The marks you're getting look more like they are coming from an issue with your pucks/compound... Are you pucks homogenous and do they have a good surface finish when they come out of the extruder? Perhaps you don't have your extruder temps set correctly. I have had this issue before and it usually resolves once you get your extruder temps and/or screw speed dialled in.

[filiperibeiro]

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.

The marks you're getting look more like they are coming from an issue with your pucks/compound... Are you pucks homogenous and do they have a good surface finish when they come out of the extruder? Perhaps you don't have your extruder temps set correctly. I have had this issue before and it usually resolves once you get your extruder temps and/or screw speed dialled in.

So why do these spots only happen when I put a label on the record? When I put a puck without a label it is always clean and there are no stains on the record.

[Aussie0zborn]

This is getting more interesting.
How about you tell us what you’re using so we’re not wasting time speculating about what your setup might be. This might give you more accurate responses.

[filiperibeiro]

ok so this is our settings of the extruder and the aspect of our 140g puck right now.

let me know if you need more information about the extruder, please.

thanks!

[Aussie0zborn]

Your PVC puck looks somewhat dry. Can you leave a fingerprint on it?

[filiperibeiro]

nope. can't leave a fingerprint on it.