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

Richard, You wrote, "I just let the records air dry vertically in a rack after wetting in the Ilfoton bath."  Many of us have found that a rinse in pure water (as defined by you, Antinn, etc) after exposure to a detergent like Ilfoton, is beneficial.  You don't want to let the LPs dry with detergent on their surfaces, or at least they will sound better if you don't. I've done the experiment, with vs without a pure water rinse (in my case deionized, distilled water from my lab at NIH, where the building supplied distilled water that ran into a huge deionizer at the main sink) made a big enough difference that I have never not done it since. Of couse, my RCM is a VPI HW17, not a US machine.

@lewm 

I gather NIH is the National Institute of Health?  I gathered you are a medical professional ... having an unlimited supply of pure water would certainly help with rinsing!

@antinn Thanks for the details.

With pure T density rho of 1 (close enough, easy math) 1g/mm3, 0.3 mg have volume of 0.0003 mm3 = 3 x 10e-4 mm3. Record surface ~ 0.3 m2 = 3 x10e5 mm2

3 x 10e-4 mm3 : 3 x 10e-5 mm2 = 1 x 10e-9 mm = 10e-12 m, which is subatomic. (Angstrom is 10e-10 m). So you have scattered molecules of T on the surface, not even a film. Thickness of impurity is that of the size of the molecule, ~ 1 nm.

As an upshot of this, rinsing with distilled water to get concentration of T down by factor 10–100x is a non-issue. It does not matter. At 100x higher concentration, "film" thickness is still in Angstrom order of magnitude, so still scattered molecules. 

Even if my calculations are not precise (record surface is 28 cm2 minus center label area guesstimated 20 cm2), our calculations give different result by factor of 10'000x, which is pretty significant, IMHO. My math skills are not that great, still don't know I passed calculus, but this looks pretty straightforward to me. 

I think the problem step is going from weight to thickness, which IMHO is not supported. Going from weight and density to volume, and volume/area to thickness is more direct. my 2c.

@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

@antinn 

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

Yes, the cheap Chinese machine I bought has a 6-litre tank.  I have not measured the record rotation speed but it is quite slow.  The unit is very noisy when operating.  I have been using two 30-minute ultrasonic sessions for each batch of records, set to a maximum of 40 degrees Celsius. 

I read version 2 of your book pretty much cover to cover a few months ago, and have not had time to do more than dip into version 3 (looking for dilution ratios)!

Before my new ultrasonic cleaning regime, I had to clean my stylus every few sides (new records left whiskers) but now it stays much cleaner.

So the records look sparkly clean, almost all my known clicks and pops have gone and the stylus stays clean.  Thanks again!