Project: - Recoating Alunimum Core from Acetates

[EpicenterBryan]

Hi guys,
I'm starting up a new thread as a place holder for some experiments. This whole thing may go on for quite a while as other people have time to play with this. I hope everyone will get involved.

Here is the background:

I discovered by accident an easy way to remove the coating from an acetate and get down to the aluminum core without any damage. Now it may be possible to experiment with applying a new cut-able surface. I don't think this works for all brands and vintages of discs so I will start compiling data using test cuts from various disc brands and vintages that I have hanging on the wall. I would love to have other people do the same with junk discs they have and post their results. This discovery may only apply to discs that were stored very poorly - I don't know.

So what happened was this: I ran across a box marked Audio discs at an estate sale (more on that later). I opened the end of the box, saw discs in there and sleeves. Removed one acetate and it was blank but had what looked like whitish mold on it - it was also kind of waxy. Many of the other disc looked fine on the ends. When I got the box back here and started inspecting the disc, all but the one I pulled out were actually already recorded on. So I thought - "Crap. There went $20" Then I decided to wash them and put them on the wall for decoration. After using my "go to" cleaner "Dawn" dish washing detergent there was no change to the surface on the first few discs. So I loaded my dishwasher with a batch but ran out of space in the washer and didn't have time to run the batch before I left. The other discs were left in the wet sink. The next day, I found the disc in the sink bubbled and had water in them. Then I discovered I could peal the disc surface right off the aluminum!

Here is a picture of a wet disc pealed off an aluminum core. It is draped over my index finger / hand.

IMG_4862.JPG

Then I dried many of the peelings and they remained as flexible. In this shot you can see what the front and rear peelings look like. I measured the thickness of a peeling and it's 0.010". I talked with the mad experimenter GridLock and he is going to see if he can cut on the back side of the peelings! I hope he will add his experiments to this thread as well.

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The aluminum cores have a waxy residue on them. So far, denature alcohol works to remove it. I'll also try some other things though. Eventually, I'm going to send Mark and John some of these blanks because I know both of them are interested in trying to re-coat them. So I hope they will eventually share results here as well.

Like I said, so far I only what discs worked using the water method and a few that do not work for sure.

What worked (that I could read a brand and code):

Storage condition: Oregon, Unknown - White waxy surface, No cracks, Box with water stains. Year recorded: 1950.
12" Presto, Numbers: 7121, 3014, 3015, 2865, 2665, 2658
10" Presto, Numbers: 3035, 2353

What has NOT worked so far:
Storage condition: Kansas, Good - Cut date unknown.
12" AudioDisc, Number 2272
12" National Hollywood - silver seal (no code)

So that's about it for now. Start experimenting people and post results!

Bryan

[Gridlock]

The blanks i got were from that sale but i didnt attend. Did you get anything other than discs?

[piaptk]

Lacquer will come off really easily using hot water. It was that cycle of the dishwasher that did it for you.

If be interested to know what could be used to recoat them.

[EpicenterBryan]

Did you get anything other than discs?

Oh man yes. An amazing sale that was. I got five Ampex 620 tube suitcase amps, tone arms, GE VR phono carts, switches, tubes, Variac, AES journals, and some well made DIY PZM Mics.

Plus, MarkRob had a shopping list and got 43 pounds of stuff. And I'm sending 70 pounds of Audio engineering mazagine from 1948 to 1966 to Alan for his reading pleasure until he moves back. And one very cool find is in one of Alan's boxes. Look closely at the name on the label. And they are blank!

IMG_4859[1].JPG

Oh, I also bought my wife these buckets of geodes. Although the purchase I made for her rocked, my Ampex amps rock much more!

IMG_4858[1].JPG

It was that cycle of the dishwasher that did it for you.

I actually didn't use the dishwasher. Ended up soaking them in the sink for 2 hours, and they came right off.

Bryan

[Gridlock]

Wow dude. Graves blanks. Ill post some pics of my scores. Audiodiscs + presto discs + "sherman hill" discs all blank. Any history on the guy whose stuff it was?

[Snakeheadfishlab]

I have taken peeled lacquer and dissolved it in nitrocellulose laquer,the stuff they use for guitar finishes and had some luck but thats as far as i have gotten.lots of bad vapors and very flammable.


Sent from my iPad using Tapatalk

[EpicenterBryan]

Here is an interesting update.
This is a disc that was marked May 30, 1941 on the back label. It came in a batch of discs I recently acquired that were blank on the other side (I have since used this one for tests). It was made by the RecorDisc corp.

IMG_4872.JPG

The interesting thing about this disc is it doesn't have an aluminum core - In fact the core is not even glass as one might expect for the WWII era. This disc has a core that a magnet wants to attract to. Once the center label was removed from one side, what looks like rust is actually glue residue. But what is more interesting is that there is no coating in the center. This disc was not coated with a curtain of goo, this disc was coated while it was spinning with goo being applied near the center leading to the outer edge.

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In this shot (hard to see) the material actually stops before the edge of the disc and gets thinner (more blue transparent looking) before bare metal is seen at the edge.

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I think this is the method I'm going to play with!

• Rotate the disc (controlling the speed to help spread the deposit)
• Use a custom overhead to deposit material starting near the center and moving toward the outer edge as being deposited.
• Control the flow rate of the deposited material and over head movement such that each "inverted groove" of material nearly over laps but not quite
• Use the RPM of the disc spinning to flow the material between each "inverted groove" of material being deposited.

In theory, couldn't we blend the deposit of the material into a smooth surface on the blank sub-straight?

For those interested, check out this segment from a "how CD's are made" video that show the rapid application of a varnish to a disc surface. This is what I'm thinking for this project - at a speed yet to be determined...

https://youtu.be/ut_40U0t9pU?t=327


Man, that's what I'm talking about.

Bryan

[EpicenterBryan]

A quick update on the disc mentioned earlier:

This disc has a core that a magnet wants to attract to.

This disc took a little longer under water, but here is the core! No other cleaning tried as of today...

IMG_4882.JPG

[EpicenterBryan]

Thursday update:

I tried a bunch of those discs from KS that didn't peal, and a bunch of others from OR and the trick is this... You just have to soak them over night. Three hours doesn't cut it, but overnight and they peel right off and leave no residue. Here is a 16" disc that was in great condition and you see it came off in one piece all the way to the edge. The trick is to scrape the edge with a blade, then get between the coating and base with a razor blade tip. Then use your finger nail to get it started and off it comes.

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Things were so successful, I decided to clear off my wall of dead test cut discs and discovered something interesting. A bunch of the discs stuck to the wall covering and left colored marks apparently from the dyes used in the Nitrocellulose lacquer / Plasticizer coating. You see blue, purple, and brownish colors. I didn't pay close attention as to which brand of disc left what color but clearly several colors were used. Some discs didn't stick at all or ever so slightly.

For those interested, the wall covering was material I was given that had metalized foil bubble wrap covered on one side with white vinyl. I used it to tone down reflections from the plywood walls in the warehouse since it was free... Check this out:

IMG_4897.JPG

The 20 or so "wall art" discs are being soaked tonight and after this batch I think I have more than enough discs in all sizes to start messing with the mechanism. Then, lots of things to read about the mixture and formulation. But I did find something I think will work for controlling the flow of the goo. Check this out. A picture is worth a thousand (of my) words. Imagine this mounted on an over head.

glue dispenser.jpg

Bryan

[Soulbear]

Hi Bryan,
I thought the "Chamber of Horrors" section, within this link might be of interest to you in respect of Blind Alleys and Cul-de-Sacs, or at least give you a smile. It discusses Gelatin and all manner of other Esoteric ingredients used in Blanks, Te He! http://www.normanfield.com/homemade78rpmrecords.htm
Regards Soulbear

[EpicenterBryan]

....Blind Alleys and Cul-de-Sacs...

I'm sure I'll run into may of my own. It should be a fun journey though.

Here is an interesting diversion that will be useful when I start messing around.

I bought a Kaman Displacement Measuring System like what MarkRob has, and today I was playing with it and decided to see if I could use this to determine the thickness of the lacquer coating on discs. Ultimately I'll need to be able to do that on my re-coated discs. After making a holder for the sensor and calibrating the system, here is how it worked!

Notice that you have to mentally shift the decimal point because of the way things get calibrated.

Here is how close the zero was set sitting on an aluminum core:

zero.jpg

Here is a peeled lacquer layer on top of the aluminum, and the thickness - Which is 5.3mil

center.jpg

Here is a measurement at the edge and also with a digital caliper. Yep, 6.2mil! My digital calibers can only resolve down to 0.5mil

at edge.jpg

last.jpg

So there you have it. A very cool device. Great find MarkRob!

[EpicenterBryan]

Items have been arriving for the machine I hope will be able to re-coat salvaged Aluminum Cores .

Parts I needed to machine are made. And tonight the base is taking form...
The legs and top base have been scavenged as well as material for the upper section yet to be cut and mounted.
The over head parts are here, as well as the dispenser.

The base now has a platter mounted. This weekend, the motor will be dropped down to clear a 16" disc.

Recoat parts.jpg

base.jpg

Now the motor needs to be mounted from the bottom so a 16" disc clears, and then for the overhead!

IMG_4967.JPG

Good, good progress...

Bryan

[diamone]

Very Nice.

For the unfamiliar - those fibre-based and colored ``lacquers'' were custom printed for dime stores drugstores and who knows how many other small merchants all across the U.S.

Most common are the Capitol series but AFAIK they came in about a dozen colors (in addition to the orange red and brown pictured, I have seen two or three shades of green, a sky blue and a midnight blue, tan and brown in addition to this sort of coffee-colored one pictured and finally yellow and purple.

From playing back dozens for transfer, I find they hold up quite well when stored properly and not allowed to dry out too bad - otherwise there's guys that specialize in rehydrating them enough to where the lacquer will NOT fall off - and other guys that specialize in removing the lacquer containing the recording off the fiber (very tricky I'm told) and then that can be played with one of those microfiber 50 milligram optical tonearms mounted above e.g. an SP 10 platter

[Gridlock]

Yeah i got old yello wilcox gay stuff that plays back awesome. Mostly grand ol opry and stuff like that. Btw anybody ever heard of GOLD TONE outta hollywood ca? Got a few one side laquers from thrift with that label on. Sixties noname psych garage stuff. Real cool. Anyway Yeah.
Bryan- i think this could possibly be where the real action is... Laquer mixes and experimenting. I definetly have a few steel style and ideas. If you understand completely the physics of whats happening and know it real good it shouldnt be a problem. ....and how to melt it all down and mix it? My humble advice as a knownothing presto nerd is to make sure that goo aint gonna leak down into yer motor there or anything. But i digress as it seems you as well have givin this some thought

[EpicenterBryan]

...and then that can be played with one of those microfiber 50 milligram optical tonearms mounted above e.g. an SP 10 platter

That was such an interesting comment, it sent me off on several days of discovery. What an interesting idea! I hope MarkRob dives into this...

For those interested - start with this fabulous video that shows the system and the block diagram.

And here are some interesting links:

http://www.christerhamp.se/phono/poliak.html
http://www.fonoteca.ch/visualAudio/publications/IASA_TechnicalCommiteeRiga.pdf
http://poliak.ch/

Bryan

[EpicenterBryan]

A mini update:

Before I spent too much time on the rotational stage, I wanted to see how fast I could run the platter with my NEMA 17 stepper at 24 volts with my home printed 100 tooth MXL pulley. So I pulled out a box I built nearly 30 years ago. Thankfully, I found my schematic from back in the day and after a few changes, was able to use it to manually run the rotary stage. Back in the day I called it "The Manual Traverse Controller".

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I set up an RPN meter and decided that the current gear ratio is not ideal. But for testing purposes, I could at least get over 200 RPM before stalling the stepper if the acceleration ramp (once I use an Arduino) is reasonable. All fine and well for testing!

IMG_4970.JPG

That's the update for tonight!

Bryan

[diamone]

start with this fabulous video that shows the system and the block diagram.

Ooh-Ooh Child things ain't gonna get no easier cuz then you get into trying to play paper records printed in a book with no grooves to follow https://mediapreservation.wordpress.com/2012/06/20/extracting-audio-from-pictures and ending up involving angular to linear calculations and the miniscule difference in linear speed from each revolution and trying to correct for it and all kinds of crazy crap.

When they could have just as easily made a photo-negative of it and treated it like an Optigan disc https://www.youtube.com/watch?v=-BVKkg7N1_g or play them all at once https://www.youtube.com/watch?v=KmP-BKYvPzg who got the idea from https://www.youtube.com/watch?v=wqzihgR_-SI (slide over to 6:40) and then guys with even MORE time than THAT on their hands ends up with https://www.youtube.com/watch?v=nOMX3deeW6Q

After which another guy gets a hair up his ass and dominates the world with https://www.youtube.com/watch?v=psuRGfAaju4

Who got followed by https://www.youtube.com/watch?v=8UVNT4wvIGY

and https://www.youtube.com/watch?v=qJlbPXZEpRE which just proves that the stupid can also get their ten minutes of fame if they want.

And then you get to asking crazy questions like What would happen if an LP and an 8 track had a baby? https://www.youtube.com/watch?v=YWI4RwSt-BU (slide over to 1:50) or a VHS and an 8 track http://videopreservation.conservation-us.org/vid_id/vcord.html or an LP and a floppy disc http://www.recordist.com/ampex/ag100.html or an LP and a wire recorder https://www.youtube.com/watch?v=U6TbxT2uTS0 or a record player and a reel to reel https://www.youtube.com/watch?v=Vd2_CrPYEY0 and on and on and on...

[diamone]

And then don't forget how desperate people can get trying for a hit record that they have to steal off the BBC https://www.youtube.com/watch?v=H6RjuRvmass (slide over to 4:54) like https://www.youtube.com/watch?v=JFfy0dMKIi8 as well as a certain X rated rapper who died of AIDS in 1995.

[EpicenterBryan]

Ooh-Ooh Child things ain't gonna get no easier cuz then you get into trying to play paper records printed in a book with no grooves to follow...

Wow. I actually watched all your links. That is one crazy gizmo I had no idea existed!
You might want to start a new thread on that. It's really interesting! I hope it becomes a perma link... Crazy interesting.

Bryan

[diamone]

Feel free. But put descriptions before the links if you intend for it to be a Sticky in the Archiving and Restoration forum so if hyperlinks suffer from Link Rot later on - people can still Google the various things we discuss.