Micro Pitting/Specks on Older Stamper Discs

[Aitchy]

Hi all,

I run the operations at a pressing plant, and for some time now we have been plagued with some issues on older stampers that have been kept in storage. Upon pulling out a set of stampers for a re-press, we will sometimes find that the stamper has developed very small specks that cover the large majority of the stamper. The resultant effect is a record that is covered in small artefacts and significant surface noise. Usually it takes around a year to develop these specks, but more recently, we have had a set of stampers that was used only a few months ago develop them.

We used to store our stampers in a basement car parking area that is technically open to the elements via the carpark gate (this is where we keep all of our materials/jackets etc.) When the issues started occurring we very quickly moved our stamper archive into the plant room indoors, which is very warm and dry. However, we are still seeming to have problems with the specks developing.

My first inkling is some sort of oxidisation or pitting is the cause. Unfortunately, it has proven impossible to rid the stamper of these defects, we have tried the usual cleaning methods as well as soaking the stampers in a dilute HCl solution. Nothing seems to work...

The confusing thing is that not all stampers will succumb to these issues, just recently I pulled out a set of stampers that was 5 years old and they were flawless, and yet some stampers that are only a few months old have degraded quite severely.

Has anyone experienced these issues? I'd love to get some feedback so I can try to prevent the issue from occuring.

Thanks in advance!

[mossboss]

Well Well Well
What you have my dear sir is nickel sulfamate which is trapped in the metal work when it is made, if the spots are greenish in colour! You can see the colour if it is really bad or under some magnification
If there is no colour than you most likely have hydrogen encapsulation with water both will eat away the nickel showing up as microdots or pits
Your or whoever is making your stampers has to get his process sorted out
Those stampers are useless scrap them, you are wasting your time attempting to recover them
Best

[Ketaman]

Obviously Nickel is generally very corrosion resistant but perhaps with you guys being close-ish to the coast maybe some of that salty air is blowing up the hill and causing some issues..? We have never had any issues with our stampers here in Melbourne and we both get them from the same manufacturer as far as I know.. Although our factory is pretty dry and our archive is upstairs in a room that stays fairly warm all year round. Maybe storing them in some big zip lock bags or getting some of that blue film that stamper discs use to protect them could be the go?

[Aitchy]

Obviously Nickel is generally very corrosion resistant but perhaps with you guys being close-ish to the coast maybe some of that salty air is blowing up the hill and causing some issues..? We have never had any issues with our stampers here in Melbourne and we both get them from the same manufacturer as far as I know.. Although our factory is pretty dry and our archive is upstairs in a room that stays fairly warm all year round. Maybe storing them in some big zip lock bags or getting some of that blue film that stamper discs use to protect them could be the go?

Yeah its quite odd! Where we are is very humid so I have long wondered if it might be due to that... It is very odd that its still happening after having moved them inside though. If it was a climate related issue then I would've thought moving them inside would have at least partially improved the problem. The fact that it seems to only happen to certain stampers too is leaving me rather stumped.

Good to know that you're not also having the same issues though, that could help us narrow down the cause.

[Aitchy]

Well Well Well
What you have my dear sir is nickel sulfamate which is trapped in the metal work when it is made, if the spots are greenish in colour! You can see the colour if it is really bad or under some magnification
If there is no colour than you most likely have hydrogen encapsulation with water both will eat away the nickel showing up as microdots or pits
Your or whoever is making your stampers has to get his process sorted out
Those stampers are useless scrap them, you are wasting your time attempting to recover them
Best

Thanks for the input! I had wondered if their might be some nickel plating defect going on, but wasn't aware of particular phenomenon that could be a problem.

Our stamper manufacturers are pretty top notch, so I'm not leaning towards them being the issue. We have sent back some stampers for sampling nonetheless, I'm sure they will be able to shed light on what exactly is happening and address the issue if necessary.

We gave up trying to revive them very quickly as it seemed fruitless, lol. We tend to just order a new set if needs be, but it would be good to find a solution to the problem.

Thanks heaps again for the input, I've got some potential leads to follow now which is great!

[mossboss]

Re reading your First post you are almost answering one of your own questions
You have 5 Year old stampers in perfect condition yet you have some months old stampers showing signs of corrosion so I doubt it is your storage conditions
Stampers and mothers will get a slight "coating" in storage that make them a little dull, this discolouration also gives them the kind of a "passivated" property which is what we do to make a stamper out of a mother
A grown stamper from an old mother will separate fine without any passivation, we don't take the risk, we always give them a slight rouge polish than a quick passivation, but we have done it more than once as an experiment or for the experience
We also have been given mothers from archives as old as you, ha, say 30+ years that showed no deterioration and many that the had the green spots on them, almost, useless but we have recovered some of them, a laborious process
By the way we did some records for the film and sound archives of the only audio artefact they have dating to the ANZAC's and Gallipoli
That was a dub plate cut in Cairo for a digger on a break from Gallipoli, who posted it to his parents here in Australia than found its way to the Archive
Interesting one
That's the oldest record we pressed here recorded Over 100 years ago
Remarkable, we all were on tender hooks during the whole time the process took making sure that the original dub plate did not get separated or destroyed
It all worked out well, we pressed some records out of the resulting metal work so they can now play them without fear of destroying the original recording
A bit of a diversion on the topic But I think an interesting little episode
Best

[farmersplow]

... so they can now play them without fear of destroying the original recording...

WOW - TOP!

[mossboss]

Greetings from Australia and thank you for the comment
I doubt that anyone in the whole wide world had the task of making a record from a 100 Year old dub plate!
So the Top comment is certainly welcome
Best