Don't waste money on ultrasonic RCMs


chayro
+1 chayro. But, in "our" defense, we are, ah, nerds? So, any statement is subject to scrutiny. 
out here on the interwebs it's a fine line between tongue-in-cheek and trolling 
There are some record cleaning fluids on the market that contain some percentage of alcohol.   People that insist on using undiluted alcohol on their vinyl records do so at the risk of damaging them over time.

DO NOT use alcohol on older 78's.  You will ruin them. 

The RCM generally isn't the issue.  It's the cleaning fluid used and the failure to adequately remove the fluid and contaminants from the record surface.

A few sources that should be reviewed and contemplated:

https://forum.audiogon.com/discussions/a-very-long-primer-on-record-cleaning-fluids

The above is VERY long - but worth the time to read.

This one is from wikipedia:

https://en.wikipedia.org/wiki/Conservation_and_restoration_of_vinyl_discs

Library of Congress:

http://www.loc.gov/preservation/care/record.html

People wanna always take shortcuts.  Methinks Mr. Tang's method of applying WD40 is just another shortcut along the lines of using wood glue.

At the very least, get yourself a Spin Clean if you can't afford a RCM
ultrasonic or otherwise.   I personally use a Okki Nokki along with Audio Intelligent Vinyl Solutions products and I'm very happy with it and the results I obtain.

Bottomline:  It's your choice.  It's your record collection.  It's your money.
Maybe I should feed the records cod liver oil. Then they'll have a nice shiny coat.
https://www.analogplanet.com/content/if-charles-kirmusss-record-cleaning-machine-and-regimen-correct...
an article from fremer's website.
The ultrasonic devices used in sealing containers or doing welding, work at 41.2-41.5khz, approximately. This is due to this particular frequency being perfect for penetrating water, as most of the fluids sealed in a tube or whatnot, are water based.
Fremer mentions the frequency of one unit being chosen to be at 35khz, and this is probably tied to the water penetration issue and cavitation and this micro porosity being introduced to the record surface via the easy to find ultrasonic devices that work at 41.2-41.5khz.