Thumbs up for ultrasonic record cleaning

@slaw 

Some other thoughts,

If you have been using the same tank of water for 5 months without refreshing the chemistry, the 'chemistry' of the Versa-Clean is likely long since exhausted and the tank water may be acidic.  Water at room temp and just warm will absorb air and CO2 which will then lead to formation of a weak acid - carbonic acid. You may be able to check the chemistry with a simple shake test - take a sample of tank water in a clean clear container, cap, and vigorous shake for about 15-sec - how much if any foam is produced, and how much is still present after 3-5 minutes.  Compare with a fresh diluted Versa-Clean.  That may give you an indication of remaining chemistry.  Also, the carbon filter only has so much soil/particulate holding capacity before break-through after which the influent (goes-in) is the same as the effluent (goes-out).  Depending on the number of records you are cleaning, using the same bath for more than 60-90 days is a stretch at best.  At worst, the cloudy condition could be the formation of bacteria.

@antinn ,

Thanks brother.

I'm in the first try with the carbon filter.I don't ever go longer than 5 weeks before replacing the water.

I thank you for posting!

@slaw 

Woops, misread your post, 5 weeks is not bad.  You may want to check  the chemistry with the shake test I discussed.  Also, Versa-Clean specifies that the cleaner is mildly alkaline pH 9.75.  You can easily monitor the tank pH with an inexpensive pH meter such as https://www.amazon.com/Accuracy-Quality-Measurement-Brewing-Laboratory/dp/B07Y32MXHY/ref=sr_1_3?dchi...

You will need to see what is the pH of a fresh tank and measure weekly to see how it drops.  Some cleaners will be 'buffered' so that the pH will decrease very slowly and then drop quickly which indicates the chemistry is depleted. 

first a word of thanks for this civil thread full of knowledge and real experience.

@antinn can you link to that “ tech manual “ on manual cleaning you refer to writing?

best to all and enjoy the music !!!!

Jim

@tomic601,

As far as my tech manual, it took a bit of turn, and it now stands at 54 pages.  The manual cleaning procedure is not very long, but I am adding a lot of details of the rationale behind various steps, cleaning agents and rinsing and I expanded it to address vacuum RCM and some discussion for ultrasonic cleaning (but not a detailed procedure), and maintenance of cleanliness with a discussion of triboelectric effect and record brushes which was a bit eye opening especially after I found a NASA study - long story short I no longer use a brush to dust, I use a piece of Kinetronics Tiger Anti-static cloth to remove (light swipe) surface dust  https://www.kinetronics.com/product/anti-static-tiger-cloth/ , and use the Audioquest carbon brush only as a conductive brush - just barely touches the surface.  The carbon fibers are very narrow and can penetrate deeply into the groove, but the carbon fibers while stronger than steel along the shaft, are brittle cross-wise and subject to breaking at the tips contaminating the groove.

At the moment I am researching chemical material compatibility since there is a lot discussion but not a lot of real data, and there is some confusion.   This is because there is so much difference between rigid-PVC such a PVC pipe, plasticized-PVC such a flexible hoses and some toys/art-works and then there is the vinyl-record which a copolymer of PVC&PVA  of which there is very little evidence of containing plasticizer.  So, while alcohol and detergents can extract plasticizer from plasticized PVC depending on the exposure time (I found two real test reports), the vinyl record does not appear to have any.   But, I did find that isopropyl alcohol even diluted down to 5% - the vapors are flammable with a flashpoint - that was a surprise.  The good thing about manual cleaning is that the record exposure time to the cleaning agents is very brief and there are no ignition hazards.  But ultrasonic cleaning can leave the record exposed to cleaning solutions for extended durations and can present an ignition hazard to flammable vapors.  FYI - distilled water is safe for extended durations.

At this point I expect to complete my tech manual in about 30-days, then I need to find a home for it - no interest in selling/making any money - just wish to give it away as a public service.