Thread: Does anyone here use ultrasonic cleaners?

Yep have been using them for decades at work and more recently at home.

Originally Posted by Pete F

I'm considering buying a new ultrasonic cleaner and wondered if others had one they would recommend? I have a small one that I bought from Harbor Freight and it's completely useless, it put me off them, but I've recently seen some evidence that (unremarkably) it was the crap product rather than the process itself that was to blame.

http://www.ebay.com.au/itm/6L-6-L-UL...item4adc08f441

I have the 3.2L version of that cleaner.
I got it with analog controls because if digital ones stuff up I am less likely to be able to fix then that analog stuff. I also find pushing little buttons to set time/temp a PITA. With a pot it's just twist and go.

We got that cleaner for SWMBO's jewellery work but I have used it much more than she has. Perfect for cleaning carby parts, bearings etc

I've seen people fill them with water and then put the small part in a bag or container and suspend that in the water bath. I'm sure there would be some attenuation in doing so, but it seems to still be effective.

There's no attenuation, in fact there is better transmission of the US waves into the object because the energy can penetrate from all sides compared to point or one sided contact . Put you finger in the water and see what you feel
In fact t is essential that they always be used with a water bath or some form of liquid coupling for any size parts or it will kill the cleaner.
That's why timers are useful because if the water dries out their lifetime shortens considerably. We lost dozens of them at work when they ran out of water.

I use the Branson brand. eBay usually has an assortment of used units. The bigger ones can be pricey but they are bulletproof. http://www.ebay.com/itm/Branson-200-...item5b075e1446

I'd be a bit careful about buying any used US cleaner as you have no idea bout how they have been used. They only have to be used a few times without liquid and they may not last that long after that.

Ok thanks guys, I doubt I'd go for a used unit in this case, indeed buying one from the US would cost almost as much in freight alone as the whole unit would cost here!! The Harbor Freight one I picked up on a trip there.

Interestingly I'd always dismissed that as useless and didn't ever use it, however this morning did a "foil test" and it actually fared quite well, much to my surprise. So I may have been a little harsh on the little thing and may experiment some more with hot water and/or different liquids.

Originally Posted by Pete F

Ok thanks guys, I doubt I'd go for a used unit in this case, indeed buying one from the US would cost almost as much in freight alone as the whole unit would cost here!! The Harbor Freight one I picked up on a trip there.

Interestingly I'd always dismissed that as useless and didn't ever use it, however this morning did a "foil test" and it actually fared quite well, much to my surprise. So I may have been a little harsh on the little thing and may experiment some more with hot water and/or different liquids.

That's good to hear. Some people are a bit impatient with US cleaners as they do take longer than we expect to do most things.

Switching back and forth several times between different liquids (alkaline/acid) sometimes helps speed things.
We used to switch between 6M nitric acid and wage rot clean metal vapour deposits off small pieces of stainless steel sheet.

No doubt you will be aware that flammable solvents will require adequate ventilation

I've been using mine a little today to clean the threads on a micrometer I'm rebuilding (making the female part). A tiny piece of metal is enough to upset the whole fit, so I need it quite clean each time I fit it. I'm finding the ultrasonic cleaner very good for that. I cleaned a few other things while it was sitting there, just using hot water and detergent. Seemed it work quite well actually, so I definitely was being harsh on it before. I'm going to delay getting a larger one until I've run this a while longer now I can see it is actually working.

I have one of the Aldi ones Pete.
For cleaning Mics i found it fantastic, either just with the soapy water or in kero. It cleaned most of the paint out of the graduations on every mic i have put in there. About the only other thing i have cleaned has been bearings, but since the aldi one is so small (500mls maybe?) there is not much else that will fit.....

Cheers,
Ew

I lashed out a year or two ago and bought a small one from Aldi, Used it once to clean up a few micrometers and now I'm embarassed to say it's never been used again.
I think from memory I wasn't all that impressed with the final outcome of the mics.

Matt

the one I have, same as peter is thinking off, is crap

A shooting collegue bought two for around 800 each (same size approx) and they are brilliant....He lent me one to try and the difference in cleaning ability and time between his and the one I bought is like "chalk and cheese"

i recall seeing a test on you tube as to tell if the one you have is effective...uses foil for the test...

Originally Posted by eskimo

the one I have, same as peter is thinking off, is crap
A shooting collegue bought two for around 800 each (same size approx) and they are brilliant....He lent me one to try and the difference in cleaning ability and time between his and the one I bought is like "chalk and cheese"
i recall seeing a test on you tube as to tell if the one you have is effective...uses foil for the test...

I don't think it's necessary to to pay that sort of money for them. Before I bought my cheapie I used to borrow a $2000 Mettle cavitator from work and my cheapie is just as effective. We went through dozens of these things at work mainly because students (and some staff) forgot to keep them topped up with sufficient water and they ran dry. For student labs we bought the cheapest units because out of the box, we could find no significant difference in the effectiveness between a $200 no-name or a $2000+ Mettler unit. The more expensive units could handle the "running out of water" aspect better but once the cheaper ones with timers becomes available that was much less of a problem.

There are other issues with these things such as RFI generation that may be significant in medical or research applications that cheaper ones may not meet and the more expensive ones probably have better HV protection.

BTW putting small parts in a plastic container in the US cleaner will not be as effective (or take longer) than if metal baskets or glass containers containers are used. We found this out when we used screw top teflon beakers to acid leach meteorites and would ultrasomicate the meteorites for a couple of hours. If we used metal or glass containers it was much faster but we couldn't do that because the metal/glass containers contaminated the samples.

You have this one and it's no good? http://www.ebay.com.au/itm/6L-6-L-UL...item4adc08f441

I've seen video of similar ones (even this one) on Youtube, and most swear by them. I watched a video of a very basic cleaner and that didn't seem to do anything.

I read a paper by a respected US ultrasonic manufacturer about buying cleaners, and they said there was no point in going above 50W (per gallon IIRC, but don't quote me on the volume figure), anyway I remember thinking all of these cleaners satisfied that power recommendation. From what I ascertain, one of the big differences between a "good" v not so good cleaner is how the power is distributed through the vessel. Even that POS Harbor Freight cleaner managed to put holes in foil, no problems at all, it was reasonably thick foil too. However I believe the better cleaners will be much more even in the ultrasonic coverage, so instead of bombing one area and another getting little, the foil test shows much more even coverage. I can imagine this would take quite a bit of research and experimentation, and is likely not found in the cheaper cleaners I'm looking at.

It seems to me the solvent, be that water or something else, is a lot more important to the whole thing that I'd thought. The increase in temperature seems to help a lot too. I dropped some diamond stones in there yesterday, turned it on, and saw that classic little "explosion" of contamination coming off the stones in the first few seconds of being turned on.

I think if I were to get a larger one I'd probably want to dedicate a place for it (I have one in mind) and have it available for use as required. I can see that if I needed to get it our, fill it up, clean it out, pack it away, it's never going to be used. I think it's a little like my parts cleaner, 99.99% of the time it its there doing nothing, but when I need it I flick the lid, use it , then go back to what I was doing.

Originally Posted by Pete F

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.I read a paper by a respected US ultrasonic manufacturer about buying cleaners, and they said there was no point in going above 50W (per gallon IIRC, but don't quote me on the volume figure), anyway I remember thinking all of these cleaners satisfied that power recommendation. From what I ascertain, one of the big differences between a "good" v not so good cleaner is how the power is distributed through the vessel. Even that POS Harbor Freight cleaner managed to put holes in foil, no problems at all, it was reasonably thick foil too. However I believe the better cleaners will be much more even in the ultrasonic coverage, so instead of bombing one area and another getting little, the foil test shows much more even coverage. I can imagine this would take quite a bit of research and experimentation, and is likely not found in the cheaper cleaners I'm looking at.

You are correct about the unnecessary requirement to have "uber power". Too much power just heats (even boil) the water so it will evaporate faster.
I doubt that distribution is an issue even on cheap units. The typically 30- 60kHz used has have a wavelength of 25-50 cm in water so a tank will have to be bigger than this in any dimension to have the possibility of a single major frequency resonance/node in the tank although there may be small effects from harmonics. Sloped tank sides and the parts themselves will also scatter the waves.

It seems to me the solvent, be that water or something else, is a lot more important to the whole thing that I'd thought. The increase in temperature seems to help a lot too. I dropped some diamond stones in there yesterday, turned it on, and saw that classic little "explosion" of contamination coming off the stones in the first few seconds of being turned on.

The oscillators are supposedly tuned for aqueous solutions but most liquids will work. We used ethanol and methanol (in fume hoods) to degrease metal and ceramic insulators before being used in HV/HV High voltage high vacuum applications. The time spent in the utrasonicator was related to the flash over voltages we could reach. We also used various acids, dimethyl chloride , chloroform - good for getting gummed up vacuum oil deposits of overheated vacuum pumps..

I think if I were to get a larger one I'd probably want to dedicate a place for it (I have one in mind) and have it available for use as required. I can see that if I needed to get it our, fill it up, clean it out, pack it away, it's never going to be used. I think it's a little like my parts cleaner, 99.99% of the time it its there doing nothing, but when I need it I flick the lid, use it , then go back to what I was doing.

SWMBO has hers put away which gives me the irrits but it's still worth getting out and using it
If you get a larger one, the units with a drain tap are useful as opposed to having to tip the large tanks over to completely empty them.

Thanks guys, the one I was considering has a tap and yes I can see how that would be beneficial.

The plastic attenuating the signal somewhat makes logical sense to me, but if the power is sufficient it's probably more than adequate to do the job anyway.

I'm basically just regurgitating what I read and saw regarding the distribution of the power within the fluid. However again it seems logical to me that not all would be created equal in that regard. Indeed it is apparently one of the main things to look for when conducting the "foil test". One of the US brands demonstrated a "sweep" mode where they attempt to provide a more even distribution. On my little fella it's very evident that the pattern is definitely not even, with a large concentration of power seemingly concentrated at one end, and then there appears to be various "nodes" (and I'm not implying any standing waves, I really haven't given it much thought in that regard), throughout the chamber.

All in all I'm pretty chuffed. I've been screwing around with an f%%^&ing dishwasher all day (they want $56 for a standard microswitch would you believe ), so I'm just getting to work in the workshop now. I expect to give the little cleaner a further workout in the process.

Thanks again

Is the Ultrasonic cleaner a good device to use to clean a set of flat slide bike carbs? Would they need to be pulled apart or could you put the carbys in complete. Also what sort of cleaning solution would be best?