ultrasound cleaning?

Since I sell ultrasonic and megasonic equipment for semiconductor manufacturing, I have considered trying to use one for LP cleaning. I have no doubt as to it's ability to perform the clean, but I have concerns about damage. I'm not saying it will, but only that it has the potential.

The cleaning mechanism in an ultrasonic is cavitation. Basically the formation and collapse of a gas bubble. At the instant the bubble collapses, the amount of energy released is very high. Typically bubbles collapse at one point and a micro jet of liquid is released at very high velocity. The energy is so high that it can damage many materials including stainless steel. Because of the damage, Ultrasonics for cleaning silicon wafers was phased out years ago and replaced by Megasonics which operate in the 1MHz range as opposed to the 25-50kHz that a typical ultrasonic operates at.

I think Megasonics would really do a great job on vinyl except for a couple of problems. The first is that they are really expensive. One that was large enough for an LP might be $35,000 or more. The other factor is that the high frequency can penetrate plastic materials and cause them to melt from the inside out. I think if you used low power and kept the vinyl moving you could probably avoid the melting, but the cost is hard to deal with.

My advice for anyone looking at ultrasonics for record cleaning would be to start with some vinyl that you picked up cheap and do some experimenting with chemicals and power if the tool has the ability to vary power. Keep the vinyl moving when in solution to minimize exposure time. Come up with a recipe that you think does a good job of cleaning and then repeat the clean a bunch of times and see if it damages the record after a number of cleans.

I'd like to do some tests at work, but the stuff we have is used for ultra critical cleans and if someone saw me with a record in one, I'd be history.

I agree with Mr. Kidnow in that I think an U/S could be made to work given the right setup, solution, and recipe.

I just question the need. The goal is to clean inside the groove of the record and the brush with suitably sized bristle tips to get down inside will do a more uniform job than the random mechanical agitation provided by acoustic cavitation.

Where the advantage of sonics is seen is when the crevice that needs to be cleaned is too small or odd shaped, or in some other way not practical to clean with a tool.

It is also true that the number of variables is greater and that to develop a cleaning process that would be better than the current proven techniques might take quite a while.

Based on what I know about ultrasonics, I don't see them as being able to remove particles any smaller than a good brush so where is the benefit?

You are correct in that no cavitation will occur without the U/S energy and no bubbles will be left behind to later implode. Once the power is turned off or the lp taken out, the vacuum dry should work just as well as if it were brushed.