@whart,
Bill what you said is correct. To amplify, Industry testing has shown that for low kHz machines (< than about 60-kHz), if the flow in the tank is >50% of the tank-volume/min the cavitation intensity drops off very quickly. As the record spins through the bath, it essentially creates flow, and the book has a calculation that considers the number of records and the rpm, and based on one or other, determines the max rpm or max # of records. However, there is a minimum rpm recommended of about 0.5-rpm otherwise depending on the UT tank power, the record may be damaged. Even with the inexpensive Chinese UT tanks, which may not produce advertised power, the bottom of the record is very close to the bottom mounted transducers where the cavitation intensity will be highest.
@gano,
Basic rule of thumb for using a single UT tank, is that for best results and best bath management, you want the record to be visually clean before UT cleaning. So, for a new record, do a simple quick brush with a soft brush to remove visual surface debris, and then into the UT tank. For used records, you want to perform a pre-clean step before final UT clean, and that can be performed with your process of choice be it a SpinClean or vacuum-RCM.
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@gano,
I want to buy the one that does most of the job. Sounds like the vacuum based would be it.
For old, used records yes. However, you still need to perform multiple steps:
Step 1: pre-clean with a detergent solution; I recommend 0.5% Alconox Liquinox (Amazon.com: Alconox - 1232-1 1232 Liquinox Anionic Critical Cleaning Liquid Detergent, 1 quart Bottle : Industrial & Scientific).
Step 2: rinse with distilled/demineralized water (DIW).
Step 3: final clean with a nonionic surfactant solution, I recommend 0.05% Tergitol 15-S-9 (Tergitol 15-S-3 and 15-S-9 Surfactant | TALAS). The final clean makes sure this is no residue left from the pre-clean step.
Step 4: final rinse with DIW
Step 5: dry
I always recommend this brush -Amazon.com: Record Doctor Clean Sweep LP Vinyl Cleaning Brush : Electronics.
Couple of things to remember:
- With vacuum RCM, you perform the cleaning, the chemistry, the brush and your technique are what cleans the record.
- The strength of the vacuum provided by the machine determines how much of the detritus released by your cleaning technique get removed. The stronger the vacuum the more that is removed/sucked from the surface. But some solution is always evaporated/dried in place. The strongest vacuums appear to leave about 10% behind while the weaker vacuums appear to leave as much as 30%. So, the 'quality' of the vacuum RCM can matter.
This vacuum RCM may be current best value - Music Hall WCS-5 Vacuum Record Cleaning Machine. It has a forward and reverse rotation and a vacuum adjustment, is of decent construction and is made in the USA. Music Hall is closing it out and you may be able to still get a good price Music Hall WCS-5 Record Cleaning Machine – Upscale Audio , Music Hall - WCS-5 - Record Cleaning Machine; otherwise Music Hall WCS-5 Vacuum Record Cleaning Machine – Audio Advice.
Good Luck,
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@tablejockey,
For the price, the HumminGuru Nova has an updated higher operating frequency
FYI, the new HG-Nova does not use a higher frequency, it's the same kHz and power as the original. Download and compare the two operating manuals: HumminGuru Owner's Manual. The Nova adds some convenience features, uses a wall-wart versus a brick power supply, and makes cleaning 45-records easier.
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@spatialking,
Theoretically, if all cleaner drains off the record, then there is nothing to dry, and nothing (non-volatile residue) will be left behind, or if the cleaner concentration is so low that no objectionable residue will remain. I am not sure what some of these vendors are marketing as a no-rinse cleaner. The exception is Osage Audio Products, LLC Audio Intelligent Vinyl Solutions Enzymatic Ultrasonic Record Cleaning Machine Concentrate which someone else tested by allowing a few drops to evaporate from a glass surface and no visible evidence of residue was noted.
Here is an example of what I have recommended as a no-rinse cleaning solution - it’s going to get technical: a cleaning solution of distilled/demineralized water + 0.005% Tergitol 15-S-9 + 2.5% of 91% isopropyl alcohol, and here is the rationale.
- Tergitol 15-S-9 is very water soluble and mixes with water very quickly and at 0.005% (same as 50-ppm) will by itself provide full wetting.
- IPA at 2.5% should (by the science) add a subtle difference to the diluted Tergitol 15-S-9. It should lower what is known as the critical micelle concentration (CMC) of Tergitol 15-S-9 just enough for the Tergitol 15-S-9 to now add some detergency. The CMC is the concentration where the surfactant has lowered the surface tension of the water as much as it can and then beyond that it provides detergency specific to the type of surfactant which in this case is nonionic which is good for oil-in-water emulsion. Additionally, the small amount of IPA helps with something called soil-roll-up. It helps to swell organic soils (i.e. fingerprints) making it easier for the Tergitol 15-S-9 to lift the soil from the surface. FYI - the CMC of surfactants varies widely; it’s a unique property.
- Additionally, just 2.5% of IPA can lower the boiling point of water from 212F (100C) to 190F (88C) which should assist with faster evaporation. FYI- adding more than 2.5% IPA does not get you much. The boiling point decreases much slower, and there is no benefit to the Tergitol, and any cleaning benefit does not show up until the concentration is now flammable which is a risk with UT machines that can 100’s and 1000’s of ml; any material compatibility issues with the machine notwithstanding.
- So, the 2.5% IPA and 0.005% Tergitol 15-S-9 are complimentary to one another.
- Pharmaceutical IPA has a maximum non-volatile residue (NVR) concentration of 50-mg/L (to do better you need to buy ACS Reagent-Grade) which when diluted to 2.5% yields (0.025)x (50-mg/L) = 1.25-mg/L. The diluted Tergitol 15-S-9 at 0.005% = about 50-mg/L NVR, and we can assume another 5-mg/L from the distilled water. So, combined, the cleaning solution is about 56.25-mg/L of NVR. If you leave worst case 2-mL (this is quite a bit) per record side, what is left after the water dries/evaporates is (2-ml) x (56.25-mg/1000-ml) = 0.11-mg of NVR on the record surface. If a simple assumption is made that the 0.11-mg of (mostly soft) residue is spread evenly across the record, the resulting film thickness is less than 0.002 microns. This film thickness is below the lowest reported surface roughness of a freshly pressed record (reports are 0.01 to 0005-microns) and at least 10X below the small modulation (0.1-micron) the stylus can reproduce.
- So, in the final analysis, even taking into account a non-uniform distribution (simple Normal (Gaussian) Distribution), with median @ 5X and peak @ 10X, the NVR left on the surface is pretty much in the record surface roughness and below what the stylus can reproduce (as sound) and is (for most) inconsequential. Additionally, in most real UT use with the record vertical, the amount that dries on the record should be 1-ml or less.
So, there is some science to this, and in no-rinse solutions, it’s a balancing act between cleaning and residue (NVR). And the experience by many along with absence of junk on the stylus supports the science. However, like all things, there are exceptions to the rules, and I have had experience with at least 1-person, who felt that that they could ’detect’ an audible difference (listening with very high-resolution headphones). They felt that there was a subtle smearing of some high frequency information. If you have ’exceptionally’ sensitive hearing and listen under the most intense conditions, add a rinse step.
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