correct sanding of the label area

[andybee]

Hi pressing guys!

In the last years, I had some problems from time to time with
the label area sanding.
The biggest problem was, when the labels stuck in some places
at the stamper.

As far as I know, there are two options for sanding:
(when the stamper is directly made from the laquer)
1. sanding the laquer before galvanic process
2. sanding the stamper

What is the correct way? In my opinion it is better, to sand the
stamper, because it can be done smooter, because the nickel
is much harder then the laquer.

Which kind of sanding paper must be used ? I have heard,
120 is the best, but it looks too rough for me....

Thanks for help!

Andreas

[Aussie0zborn]

Andy, in the old days EVERYBODY sanded the lacquer in the label area and the outside edges. There is a benefit in the glavanics too, if you do this.

Where the silvering is not perfect or the nickel solution is not perfect, it is possible for the nickel build-up to strip away from the lacquer in these un-sanded areas.

There were as many ways of sanding the lacquer as there were people doing it but I took the advice of an old man and used a rubber ink eraser to sand the label area on the lathe's turntable. It roughens it sufficiently to stop the label from slipping and cracking yet has a smooth enough finish to still make the label look good.

If the label sticks to the stamper, then it has not been dried properly or you are using colours such as gold or silver. Roughening the label part of the lacquer is to stop the label from cracking. Let us know how you go.

http://www.jrbourne.com/index.asp?ProductId=35&ProductTypeId=15

[mossboss]

Scuffing the lacquer with emery paper or cloth is a bit so and so done carefully while the lacquer is wet is OK
However the guys in the galvanics get a little slack some times where they do them dry Than it is an issue
Bits come off get in the cut some times very hard to get them out than one has clicks and pops
Doing it on the stamper is also a pain as it has to be done with the good side up a source of mishaps
Best solution we found is this:
Rough Scotch pad green in colour
Cut it round to suit the label area 7" or 12"
Mounted in a wooden round block than scuff the lacquer when it is on the silvering t/t
Make sure the Scotch pad is wet, most issues are minimised, result is always good
The pad that is used to polish vinyl floors on these big rotary floor polishers is also very good
The medium rough stuff white in colour
I think the colour of the pad denotes the grade
Cheers

[montalbano]

Hey Andi
There are many different ways to do this and this is not only related to one-stop shops like we are, I have seen galvanic suppliers supplying stampers without any sanding in the label area as well.
We always do this job on the lacquers in a very similar manner to what has been described by Mossy.
The fact that the labels tend to stick is not the only problem, because in most of these cases you will see that if the label area has not been correctly sanded, especially in its diameter, the labels will tend to break during the pressing. Unless of course the speed of your press has been slowed down very much.
It is curious to observe that if you have two stampers both with non polished or not enough polished label areas, the first label which will tend to break is the label in the top mould. You fix the stamper mounted in the top, and then the label in the bottom, which right before didn't break, will tend to break. So you will have to fix both of course.
Anyway we have got the best results by cutting 9.8mm of scotch-brite glued to a little PVC disc of the same diameter. Both drilled 7.3mm in the center and put directly on the spindle of the silvering TT right before the washing cycle before the silvering starts etc.
If you are working with supplied stampers, try to do this while they are wet, there is a minimum "scratching" which has to be applied, regardless, especially to avoid the breaking of labels. If you are going to use two different kind of emerys, say a 280 for the center and a 600 for the edges, it wont work. A 600 is too fine. Wash them very well after the job has been done.
I have been supplied many times with DMMs, and I have always noticed that the label area is already "prepared" with parallel spaced grooves. I always wondered whether this is an extra function of the VMS82 or something done afterwards. They really look as cut grooves so I suppose it's the Neumann doing the job...

[Aussie0zborn]

DMM masters have the label area roughened by hand just as lacquers do.

[andybee]

aaah, thanks for this lot of useful infos, now I see more clear
I had also this effect, that only the label on the top mould was broken,
after fixing the bottom.
I dryed the labels always correctly, the effect comes 100% from
the stamper.
The VMS 82 has an option to cut a very thin empty groove at the
label area.
you can see it here in a video:

http://www.youtube.com/watch?v=HocWBv1g_fo&feature=related
at 8:44 (green arrow)

thanks again

[Serif]

As far as I know, there are two options for sanding:
(when the stamper is directly made from the laquer)
1. sanding the laquer before galvanic process
2. sanding the stamper
...

Just like lacquer cutting is actually Grandmothering (since the metal negative is a Father), or embossing is actually impressing, if pushing down from above (rather than up from below), there appears to be another common word-swap in mastering when it comes to electroforming the matrix, mother, and stampers, which is actually reverse-Galvanics, yes?, since the Galvanic cell is actually a battery. Whereas the electrodeposition is going on in a battery-charger (secondary cell), sort of tank (not a battery which dis-charges, itself, like a primary cell). But Galvanics is more fun to say than electro-deposition.

Also, there is a better way than sanding to handle the label scuffing, but if the VMS 80 can make furroughs, there, that is cool, Andy! (L:



- In lieu Ouja Gal Gadon't

[Aussie0zborn]

But Galvanics is more fun to say than electro-deposition.

The electro-deposition process that you speak of was invented by a certain Mr. Luigi Galvani and naming the process after himself, the correct term is actually Galvanic. So not only is it more fun to say, but it's more correct too.

[Serif]

But Galvanics is more fun to say than electro-deposition.

The electro-deposition process that you speak of was invented by a certain Mr. Luigi Galvani and naming the process after himself, the correct term is actually Galvanic. So not only is it more fun to say, but it's more correct too.

Sorry, Aussie..., but you need to check your electrodes... (Did you not see my last nom de plume in the post to which you are replying? In lieu Ouija Gal Gadon't? This reads, /in lieu-igi Gal ga don't).

Galvani was using bath water to make a frog's legs jump. In electrodeposition, one is using something not unlike a frog's legs (i.e., outside energy) in order to make ions move in the bath water...

From Wikipedia:

"The process used in electroplating is called electrodeposition. It is analogous to a galvanic cell acting in reverse..." 0:

You must have conflated this Luigi with another?

Also, from Wikipedia: "...Modern electrochemistry was invented by Italian chemist Luigi V. Brugnatelli in 1805. Brugnatelli used his colleague Alessandro Volta's invention of five years earlier, the voltaic pile, to facilitate the first electrodeposition..."

Grüß Got,
- Seraø

[Aussie0zborn]

Sorry Serif, but I'm not convinced that your nom de plume adds up to "Luigi Galvani".

School children in Australia know not to use Wikipedia. I'm surprised a learned man and fine wordsmith such as your good self would rely on such a resource.

Technically, I think you may be correct but I say that when using European equipment, one should use the terminology adopted by the Europeans. Given their technical superiority in the world of galvanics for record pressing, I think they deserve this one.

[Angus McCarthy]

"Galvanized" metals of any kind have gone through an electroplating process. Auzzie's got it right on this one.