My version of an Ultrasonic Record Cleaner

[78RPMcollector]

My wife does not see why I need to spend hundreds of dollars on a record cleaner. You've just solved my problem. The only caution I would add is that 78RPM (shellac) records should not be exposed to alcohol. It dissolves them. Better to use an extremely dilute dishwashing liquid (the brand they clean oil-soaked birds with) on 78s.

[78RPMcollector]

Originally Posted by bbftx

Hi Shaun,
The 60khz cleaner is a Sonix IV machine (6 quart version).
Warning: The fit and finish of the machine is terrible for a $500 item. I almost sent it back. (examples: control panel label wasn't put on flat and in the proper location. There were large, uneven lines of silicone sealant underneath the lip of the tank at the joint between the tank lip and the surrounding metal case.) But these problems don't affect function.
It works extremely well in it's functionality as a cleaner. So I kept it, and in the nature of DIY, fixed some of the problems myself--- e.g. it needed taller rubber feet so the drain valve is clear of the surface on which the unit sits.
The standing waves in the bath definitely are closer together and distributed better throughout the liquid than those in most 40khz units I've seen. And as I said, it did very well cleaning the jewelry I put in it. So, for me, it was worth the cost. But I want to make sure folks don't expect "Mercedes-level fit and finish" if they go down this path.

I looked into some 80khz units, like Zenith Ultrasonics makes, but these start at $1400 for a basic unit. Too expensive in my opinion. I get most of the benefits of higher frequencies at the $500 price point.

Shaun, here are my calculations: Sound travels at 1497 meters/sec in water at 25 degrees C or 4871 ft/sec at 70 degrees F. Depth of groove is 0.0029” = 2.417e-4 ft. = 0.0002417 ft (see KAB Electro Acoustics http://www.kabusa.com
4871 / .0002417 = 20.16 kHz. Since you might want two wavelengths into the groove to knock out smaller particles, you get about 40 kHz. Vinyl is very resilient and hard to damage. I once bent a 33 rpm vinyl record to try to break it. I bent it into a full U shape upon which it finally exploded with a loud retort sending shards into the wallboard. Fortunately, none of them hit my face. 78 rpm shellac records are brittle and have grooves twice as deep. One might want to keep the db level lower to avoid damage -- or sacrifice one 78 to see what causes damage.

[bbftx]

Originally Posted by 78RPMcollector

Shaun, here are my calculations: Sound travels at 1497 meters/sec in water at 25 degrees C or 4871 ft/sec at 70 degrees F. Depth of groove is 0.0029” = 2.417e-4 ft. = 0.0002417 ft (see KAB Electro Acoustics http://www.kabusa.com
4871 / .0002417 = 20.16 kHz

Hi 78RPM,
You're off by 3 zeros. You get 20.16 MHz.
The wavelength in water for these UC machines is 3 inches at 20kHz and 1 inch at 60kHz.

But wavelength is NOT the driver of cleaning penetration on a grooved surface in an ultrasonic cleaner.

Ultrasonic cleaners clean based on the cavitation bubble size, which is much, much smaller than the wavelength of the driving frequency. See the attached chart showing Dependence of the Bubble Radius upon Driving Frequency. The cavitation bubble in a 60 kHz machine will have a radius of about 5 microns. The radius of a 78 stylus is roughly 70 microns (0.0027 inches or 2.7 mils), MUCH larger than the size of the tiny cavitation bubbles.
A 33-1/3 rpm stylus has a tip radius of about 17 microns to 25 microns, so again, the 5 micron cavitation bubbles can easily get into the grooves of a modern LP.
I'll also repost the graph here showing the particle size removed based on frequency. Note the scale range of 0.3 to 7 microns (roughly our bubble size).

BB

[Vinyladdict]

So it's been pretty quiet in this thread lately so I thought I would give an update on what I call my "Budget Build".

I call it that because I was unable to source a gently used 60KHz ultrasonic machine to use as my base and was looking at well over $600.00 (after taxes and shipping) to get my hands on a Sonic IV or Gemoro 60KHz machine. Being an impatient SOB I decided to take a flyer on a 40KHz machine and was able to find a brand new one for $259.00 including shipping on ebay. I have acquired all of my parts (thanks BBTX for the parts list) except the 6 RPH motor that was back-ordered from H&R. It is supposed to ship tomorrow. I spoke with the manufacturer of the motor and they said that they custom build the motors for H&R and that there is no other re-seller of those products. In the meantime I wanted to clean some records so I suspended the loaded spindle between two pieces of Styrofoam that the cleaner shipped with and gave the records a spin every four minutes.

I have to say that the 40KHz machine seems to work just fine. The results have been great with no damage to the vinyl. I had a few nasty, moldy records to use as a test. One Beatles album I picked up in a garage sale collection was so bad I had to peel the original paper record sleeve off before doing a test clean. A 12 minute cycle got almost all of the crud off. I used a carbon fibre brush and some cleaning solution to manually go over the problem spot, then back in the machine for another 12 minute cycle. The record came out sparkling clean and sounded great when I played it a while later. I am completely sold on this method of cleaning.

Once I get the motor installed I will take more photos and assemble a complete cost sheet but I think my total cost outlay will probably come in around $320.00. I am already thinking about my next machine that will have an increased record capacity.

Thanks again to everyone who has contributed to this thread, especially BB who has provided so much valuable insight.

[78RPMcollector]

Hi, Vinyladdict, that's good news. Why not try a gearhead motor such as this one which gears down motor speed to 4.5 RPM? see www.jameco.com Jameco Part no. 155821. You can gear down even more by visiting your local hobby shop and getting gears and pulleys made with Lego blocks. OR-- you could run it at a lower voltage than 12VDC to get slower speed -- OR -- you could put an inexpensive Pulse Width Modulator (L298 motor controller from CanaKit, $19) on it to run at slower speed -- OR -- you could put an NE555 timer on it to turn for a fraction of a second, pause, turn again, pause ... Any of these methods is cheaper than the solution you found so far.

They (Jameco) also have a 40kHz transducer, Matsushita EFR40K2, Jameco Part no. 2120268. Do you suppose we could wrap this transducer in a plastic bag and immerse it in water to provide the ultrasonic wave? Am I naive here?

[bbftx]

Originally Posted by 78RPMcollector

Why not try a gearhead motor such as this one which gears down motor speed to 4.5 RPM? You can gear down even more by visiting your local hobby shop and getting gears and pulleys made with Lego blocks. OR-- you could run it at a lower voltage than 12VDC to get slower speed -- OR -- you could put an inexpensive Pulse Width Modulator (L298 motor controller from CanaKit, $19) on it to run at slower speed -- OR -- you could put an NE555 timer on it to turn for a fraction of a second, pause, turn again, pause ... Any of these methods is cheaper than the solution you found so far.

78RPM - with all due respect, none of those options are cheaper than the Synchron motor, which is $19.95, and operates at the optimal output speed of 5 to 6 RPH without the need for additional gears, pulleys, or another gearbox to contain those additional parts, or a DC power supply. A 115 VAC motor like the Synchron is much more cost effective.

And no, simply putting a transducer in a liquid bath won't work.

[bbftx]

Originally Posted by Vinyladdict

The results have been great with no damage to the vinyl. I had a few nasty, moldy records to use as a test. One Beatles album I picked up in a garage sale collection was so bad I had to peel the original paper record sleeve off before doing a test clean. A 12 minute cycle got almost all of the crud off. I used a carbon fibre brush and some cleaning solution to manually go over the problem spot, then back in the machine for another 12 minute cycle. The record came out sparkling clean and sounded great when I played it a while later. I am completely sold on this method of cleaning.

Addict - Glad to hear things are coming along. What mix of cleaning solution were you using for your first experiments?
BB

[Vinyladdict]

Hi 78RPM,

I appreciate your suggestion for alternate motors but the unit shipped finally shipped yesterday so I will continue spinning by hand until it arrives. I am a DIY noob and I am a big fan of not reinventing the wheel. In this case I have been fortunate to have received the benefit of other DIYers experience. I am assuming your tongue was firmly planted in your cheek when you suggested the transducer in the bag method?

[Vinyladdict]

Originally Posted by bbftx

Addict - Glad to hear things are coming along. What mix of cleaning solution were you using for your first experiments?
BB

Hey BB,

I started with your latest recommended mix - 150 oz distilled, 3 OZ IPA, and .2 oz of Triton X-100 instead of the photoflow. It seems to work quite well although I think on really dirty records I get from garage sales I will have to change the solution more often as the last few records of last nights batch sounded a bit fuzzy/distorted. I ran them through clean solution this morning and they sound great.

I may reduce the Triton X a bit as I seem to get some suds when I Degass and I am leery about the the air-drying part of the cycle.

I am attaching a photo of crud in the tank.

[bbftx]

Originally Posted by Vinyladdict

I am attaching a photo of crud in the tank.

Wow, that is some crud, alright! Do you have any "before" pics of the record?

I haven't used Triton X-100, so don't know how much is best. I wouldn't assume you'd use the same amount of Triton as if you're using Kodak Photo-Flo 200. Definitely needs to be reduced if you're getting bubbles. Seems like people are usually talking about using a few drops of Triton, not more than that.

The amount of either Photo-Flo or Triton needed can also be different depending on the water you're using.
B B