ultrasound cleaning?

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.

The contributions of folks like Ogsarg and Mrkidknow who can offer salient and knowledgeable information on a not so well understood process is what makes this site great. Obliged.

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?

Dougdeacon,

No problem in at least trying to contribute on this subject.

Although I have strong reservations about using ultrasonics on vinyl, this doesn't mean that a system cannot be designed that is quite safe. Bent Audio and any other companies that are investigating this must be putting a good amount of time and observation into the concept in order to eventually know if their product will be safe or not.

I just have serious concerns that the number of variables that can be missed in product developement will come back to haunt users. Due to the likely high cost of such equipment, those users will be pissed-off bigtime is something does go wrong.

Personally, I'll stick with brushing and vacuuming since it is an already proven technology.

Mr. Kidknow

Ogsarg and Mr. Kidknow,

MANY thanks for your input. As one who has been interested in the pending U/S RCM from BentAudio since it was first announced, I'm paying close attention. I'm going to point this thread out to John Chapman so he can consider the issues you've raised. (one hopes he has done so already).

If I got such a machine, I'd clean a junk LP repeatedly, increasing cleaning times and/or intensities to test for possible vinyl damage. IOW I'd *try* to wreck the LP, just to learn the limits for safe use.

As I mentioned, the design does keep the LP moving so that should help, according to Ogsarg. I believe it may also include a rinse tank.

Spinitch, if anything was left behind on the record it would just be some of the solution. If it's safe for vinyl it's hard to imagine it could damage a stylus. No exploding bubbles (imploding actually) once the U/S energy is turned off.

I have to agree with Ogsarg that there is strong potential to trash an LP via ultrasonic cavitation.

I formulate water-based cleaners for aerospace and general industrial cleaning. The majority of these cleaners are used in ultrasonic tanks.

Several parameters are relevant to preventing damage;

1. Duration of exposure to ultrasonics - leave the parts in too long and erosion damage can occur, especially on softer substrates.

2. Frequency choice - if ultrasonics is to be used on an LP, you cannot use 20-25 kHz. A good starting point would be 40 kHz but even higher is better. As the frequency is lowered, the cavitation becomes more violent. Never clean aluminum in a 25 kHz ultrasonic tank because you will literally tear the metal apart. 40 kHz is safe on aluminum as long as the exposure time is not excessive; try to limit exposure to 5 minutes max. Vinyl is softer than aluminum so I would be very concerned about even using 40 kHz. However, 40 kHz can still be safe if the power input is low. There are also ways to mediate the cavitational energy through racking and cleaner design, etc.

3. Temperature - only clean at room temperature on vinyl but this should be obvious because heat will warp records. Industrial ultrasonic cleaning is often run at 120 - 170°F.

4. You generally want to use a foamy cleaner because a foamy cleaner enhances cavitation. An aqueous cleaner that becomes cloudy when diluted and is low foaming will not yield as good cavitational performance because the design does not enhance cavitation. Conversely, a low foam cleaner can still work, especially if it dampens cavitation just enough to minimize erosion of the vinyl.

5. A rinse step should follow the wash step if possible which adds another tank.

There probably are a couple other factors worth going into but I'll leave it as is for now.

I think this instrument will be too expensive to be practical for nearly all vinyl lovers. I think the potential to screw-up the record is too great. You would be better off buying or custom building a vacuum cleaning unit and using a good commercial cleaner such as the RLL product line than to venture down the road of ultrasonics.

Mr. Kidknow

Good stuff on the dangers of US. I was almost going to go buy one this w/e.

While I would not want to damage a record, if that is the only risk, I might be able to live with it. For replaceable records and maybe forgoe for the special ones. However, if a micro-bubble could remain behind and damage a stylus, then even if remote risk I would be much less inclined to consider. Is stylus damage possible? Or is it mainly the record which risks damage?

If stylus damage is possible is there a time period after say washing/drying/vacuum etc... where risks dissipates. In which case could do ultra-sound clean then, wash/dry then putaway. Play l8r.

Again, thks for info.

Good site for additional pics of the Asia model.

http://www.asahi-net.or.jp/~zi2a-hsgw/usonic.htm

click on the links to see various profiles.

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.

John Chapman's design is interesting. You mount up to 7 LP's on a sort of rotisserie spit, kind of like baking a chicken. :) The motor rotates the records VERY SLOWLY through the bath. Only the bottom portion of the records is submerged, and the motor goes so slowly that the solution slides off the record and doesn't wet the label. John suggests a 5-10 minute cleaning cycle. No vacuum included, so if that proves necessary a second device will be needed.

[email protected],
What solution do you like best? How necessary is vaccuming.

Greatly appreciate the suggestion and feedback on the effectiveness for this technology.

I am eagerly waiting to see John Chapman's invention suggested earlier. Why? A slight digression, but Coz very strangely on same day, different forum, he was suggested on another product I am very interested in FAL speakers. These are full range single driver speakers. I stumbled upon, literally, shopping for other equip. What was meant to be a quick view 5mins, turned out to be an enlightening after-noon.

The VPIs are nice but very expensive in Japan 2X US prices and since heavy will cost a bit to ship from US. I believe I can make a vacuum machine with nominal effort/cost.
http://www.teresaudio.com/haven/cleaner/cleaner.html

The ultra-sound LP cleaners in Japan are not much more than an off the medical/optical cleaners, but have base brushes, spindle and label cover included. Costs $200+ for the motor to spin, which I am struggling with the value on something so simple, but alas convenient.

Well I am leaning towards one of these devices, whether Chapmans, the JP model or medical/optical machine. Just want to increase my comfort level they are worth it.

I am personally using a ultrasonic bath tan for cleaning medical/dental supllies in cleaning LPs. They are great. Buy one large enough and it would not caused more than 300. After that , get a VPI 16.5, vacumn dry the LPs. I assure you, this will be cleanest LP you ever have.

There is an article in recent Dec-03 issue of Analog(Japanese magazine) on this machine. More pictures and explanations, specs. I can do my best to translate/summarize(will take some time though). But can not share photos due to copyright stuff. I will see if Analog magazine has a web-site of course will be in Japanese but at least can see. It has a + (cross) on the bottom each with 2 brushes on each of the 4 arms top, bottom, left, right, seems they are offset to provide full coverage. There is a manual unit and an automated for spinning. about $200 dif.

More to come. I may be the guinea pig. If I can confirm these types of devices are really effective. I have read varying opinions. Most say concept is sound:) but overkill and regular washing is just as good with vacuum most important. One person mentioned a concern over micro bubbles left over, could theoretically damage stylus, but not sure anyone has ever experienced. Stylus are more expensive not to mention the hassle of getting installed.

I haven't heard of those before, and my Japanese is nonexistent. Any chance they have an English site?

John Chapman at BentAudio is working on an ultrasonic LP cleaner. He showed a prototype at VSAC but he hasn't released it yet.

I'm waiting like you...