Record Cleaning Using Vacuum Machine for Cleaning and Ultrasonic for Final Rinse

@billstevenson,  Bill, I am not sure if you took what I wrote in Chapter XIII out of context.

The records are vacuum dried because Neil reported finding 10%-30% residual solids left on the record surface using air drying techniques.  So it is important to get the debris off the record while it is still suspended in the cleaning fluid.  I use a microfiber towel to dry the turntable on the Cyclone between each side of the record during drying.

The blower-style vacuum-RCM (such as VPI) does not suck-up all fluid from the surface.  Anywhere from 10 to 30% is essentially dried/evaporated in-place.  So, it's important to final rinse after using cleaning solutions.  It's OK to use the vacuum to remove the cleaning solution and even if some is dried in place, the Alconox Liquinox pre-cleaner and the Tergitol 15-S-9 rehydrate and go back into solution when you rinse.  There is no reason to use a microfiber cloth to remove the cleaning solution.  

Let me show what happens with Tergitol 15-S-9 when its applied at the recommended 0.05% concentration = 500-ppm which also equals 500-mg/L (same as 0.5-mg/ml).  Let's assume you are applying 7-ml of fluid to the record surface:

1. If of 7-ml applied 0.05% Tergitol the worst case 30% dries in-place, that's 2.1-ml and at 0.5-mg/ml, 1.05-mg of Tergitol residue is on the record.
2. 7-ml of rinse water is applied, and now the 1.05-mg Tergitol is diluted to 1.05-mg/7-ml = 0.15-mg/ml.
3. If of the 7-ml rinse water (with some Tergitol) applied the worst case 30% dries in-place, that's 2.1-ml of 0.15-mg/ml Tergitol and now the Tergitol residue is down to 0.315-mg.  
4. Assuming the 0.315-mg is uniformly spread across the record, the residue thickness is ~0.0315-microns and this is down at inherent surface roughness making it inconsequential.  
5. If you wanted to be very conservative, you just do a 2nd final rinse

Hope this is of some help,

Take care,

Neil

@billstevenson,  Bill, thanks for the clarification.

Take care,

Neil

@oberoniaomnia, 

how do you get from mass of pure dehydrated Tergitol to film thickness of 31 nm? Tergitol is something like a C33 hydrocarbon chain and generally hydrocarbon chains are around 1 nm thick (e.g., sugar). I failed to find any information on volume of dry Tergitol.

First is does not dehydrate, as a 100% concentrate - it's an oil with very low vapor pressure and a specific gravity of 1.006 g/ml TERGITOL™ 15-S-9 Surfactant which is essentially the same as water. 

There are a number of ways to calculate the record surface area.  A close estimate is the surface are of the flat portion, the groove area and the side-wall ridge groove area.  A simple groove length estimate is assuming an average groove velocity of the outer and inner grooves ((51-cm/s + 20-cm/s)/2) = 35.5-cm/s times a playback length of 20-min (1200-sec).   The average groove dimension of the 45-deg groove wall triangle hypotenuse is about 0.0016-inches so that each groove has about 0.0032-inches linear length that is about 0.0022-inch wide at the top and then add 10-15% for the side wall ridges,  Run all the numbers, and the surface area including grooves and side-wall ridges is approximately, close-enough, to 1-sq-ft, which make the film thickness analysis easier.  

The non-volatile residue (NVR) nominal film thickness (Contamination Control Engineering Design Guidelines for the Aerospace Community, NASA Contractor Report 4740, May 1996)  assumes the contaminant is uniformly applied and has a density of 1-g/cm³ = 62.43 lbs/ft³ (same as freshwater); and while a 1-micron film calculates to about 9.1 mg/ft², for ease of use 10 mg/ft² equals 1-micron thickness is used which is proportional.  Most water-soluble nonionic surfactants have a density very close to water, but much lower density contaminants will develop larger film thickness while denser contaminants such as hard water spots develop thinner thickness.  

I do a deep dive into the whole subject of “What is clean?” and for a record “When is a vinyl record clean?" in this free book -Precision Aqueous Cleaning of Vinyl Records-3rd Edition - The Vinyl Press Chapter XI which is pretty technical but given your background you should be able to wade through it.   

Enjoy,

Neil

@richardbrand,

Thanks for the compliment, but not exactly a labor of love.  I started that project during COVID when I was retired (not anymore), and it kept me occupied and my skill sets sharpened.  And thanks to meeting up with Bill Hart @whart he stepped in with many good suggestions and as Publisher allowing the book be offered free through his site.  

Otherwise, I am not horrified by your use of Brita filter to deionize your good tap water.  First, the book makes not specific recommendation of distilled water.  The acronym DIW means demineralized/deionized/distilled water.  It just so happens that distilled water is plentiful and cheap in the US, while in the EU/UK demineralized/deionized is plentiful and cheap.  Neither provides any benefit over the other for record cleaning.  Second, the book offers a similar suggestion in Chapter VII.4.2 There are a number of vendors manufacturing countertop pitcher/filter systems that can produce Purified water. The ZeroWater™ units Water Filters & Water Filter Pitchers - Clean Water at Home | Culligan ZeroWater have the benefit of containing the most amount of demineralizer resin. Amazon.au sells ZeroWater Official Replacement Filter - 5-Stage Filter Replacement 0 TDS for Improved Tap Water Taste - System NSF Certified to Reduce Lead, Chromium, and PFOA/PFOS, 3-Pack : Amazon.com.au: Sports, Fitness & Outdoors but not cheap.  

Otherwise, assuming you bought a 6L UT tank reducing the number of records to no more than three and space them out about 25-cm and slowing the rotation speed to about 1.5-2-rpm should provide you with a cleaner record.  Most of the Chinese unit spinners are 24VDC and you can easily purchase a variable power supply to slow the rotation such as SHNITPWR 3V ~ 24V 3A 72W Power Supply Adjustable DC 3V 5V 6V 9V 12V 15V 16V 18V 19V 20V 24V Variable Universal AC/DC Adapter 100V-240V AC to DC Converter with 14 Tips 5.5x2.5mm 4.0x1.7mm 3.5x1.35mm : Amazon.com.au: Electronic.

Take care,

Neil

@oberoniaomnia,

The density (rho) of Tergitol is not 1, its specific gravity is essentially 1, so it's the same as freshwater which is 62.4-lbs/ft^3, convert to mg/cm^3 = 28,304,164-mg/28,316.85-cm^3 = ~1-g/cm^3 = 28,316,846-mg/ft^3.

How did you get only a surface area if 20-cm^2.  The record is 12"-D (113.1-in^2) minus the 4" D label area (12.6-in^2) = 100.5-in^2 = 648.4-cm^2.  Plus, you have to add the area of the grooves.    

1-micron (0.0001-cm) thickness across a 1-cm^2 surface = 0.0001-cm^3.  

1-micron (0.00000328-ft) thickness across a 1-ft^2 surface =0.00000328-ft^3.  

1-micron of surfactant with density of 1000-mg/cm^3 spread across 1-cm^2 surface = (1000-mg/cm^3 x 0.0001-cm^3) = 0.1-mg.  

1-micron of surfactant with density of 28,316,846-mg/ft^3 spread across 1-ft^2 = (28,316,846-mg/ft^3 x 0.00000328-ft^3) = 92.879-mg.  

So, my calculation is off by a factor of ~10.  In my book, I show 1-micron to be 10-mg/ft^2, when in fact is ~100-mg/ft^2.  So, 1-mg/ft^2 is not 0.1-micron but 0.01-micron.  Reviewing the NASA document I found my error.  They show 1-ug/cm^2 (1-mg/0.1-m^2) for contaminant 1-g/cm^3 = 10-nanometers = 0.01-micron; and 1-mg/0.1-m^2 = 1-mg/ft^2.

Take care,

Neil

@richardbrand,

If you are spinning 9-records in a 6L tank, there are 2-problems - too much mass in the tank and you are overloading the tank, and even at a slow spin speed you are developing enough fluid flow/motion to pretty much kill most cavitation energy.  As the book addresses, if the flow in the tank is >50% of the tank volume/min, the ultrasonic cavitation energy drops quickly.  Try 3-record space ~25-cm apart and spin for 20-min.  I suspect you will get good results, and the time to clean 9-records would be the same at 1-hr.

As far as dilution ratios, it's in Chapter XIV, but it's a bit spread-out, but here they are for Polysorbate 20 and your 6L tank

• No rinse, wetting only:  0.0035 to 0.0050% (0.2 to 0.3-ml).  Adding 2.5% IPA has some limited benefit in getting a little better wetting, but add the IPA after adding Polysorbate 20 or the Polysorbate will not dissolve quickly
• No rinse, with some detergency 0.008% (0.5-ml).  Adding 2.5% IPA can help with the getting a bit better detergency but add the IPA after adding the Polysorbate 20 or the Polysorbate will not dissolve very quickly.
• Rinse recommended, full detergency:  0.0150% (0.9-ml).  Adding 2.5% IPA to this has limited benefit.

If you can buy the Nalgene Dropper Bottle at a low price - Nalgene Drop Bottle (2-Ounce) : Nalgene: Amazon.com.au: Sports, Fitness & Outdoors, it delivers 0.04-ml/drop.  Otherwise, assume an eye drop will deliver 0.05-ml/drop.

Good Luck,

Neil

@orthomead,

Below is Figure 39 from the book that shows the change in surface tension of Ethanol and IPA.  There is not much difference between the two.  To get an appreciable surface tension decrease about 5% is required.  The record surface tension should be about 36-37 dynes/cm.  Getting the water surface tension close is enough to 'wet' the record.  

 Figure 39 – Water + Alcohol Surface Tensions of at 25°C from PACVR
(adapted with permission copyright 1995, American Chemical Society)

 Data for Figure 39 is from “Surface Tension of Alcohol + Water from 20 to 50°C”, Gonzalo Vazquez, Estrella Alvarez, Jose M. Navaza, Journal of Chemical and Engineering Data. 1 May 1995.