collapse


* User Info

 
 
Welcome, Guest. Please login or register.
Did you miss your activation email?

* Who's Online

fishboy3@telus.net

Dot Guests: 170 | Dot Users
Dot Hidden: 0

* Board Stats

  • stats Total Members: 12788
  • stats Total Posts: 127134
  • stats Total Topics: 17770
  • stats Total Categories: 5
  • stats Total Boards: 48
  • stats Most Online: 814

* Advertisers

Gear Pan
The lil Gold Spinner
The lil Gold Spinner
The Pocket Sluice

Author Topic: Ultrasonics  (Read 310 times)

0 Members and 1 Guest are viewing this topic.

Offline snowman18

  • Jr. Member
  • ***
  • Posts: 51
  • Province/State: BC
  • Country: ca
  • Kudos: 5
Ultrasonics
« on: November 05, 2018, 09:57:44 AM »
For no reason, I'm doing some research in the filed of ultrasonic transducers and thier uses in metallurgy when I came across an article on synthetic diamonds.

Ultrasonic Cavitation Ultrasound in liquids causes locally very extreme effects. When sonicating liquids at high intensities, the sound waves that propagate into the liquid media result in alternating high-pressure (compression) and low-pressure (rarefaction) cycles, with rates depending on the frequency.

During the low-pressure cycle, high-intensity ultrasonic waves create small vacuum bubbles or voids in the liquid. When the bubbles attain a volume at which they can no longer absorb energy, they collapse violently during a high-pressure cycle. This phenomenon is termed cavitation.

During the implosion very high temperatures (approx. 5,000K) and pressures (approx. 2,000atm) are reached locally. The implosion of the cavitation bubble also results in liquid jets of up to 280m/s velocity. (Suslick 1998) It is obvious that micro- and nano-crystalline diamonds may be synthesized in the field of ultrasonic cavitation.

Read more: https://www.hielscher.com/ultrasonic-synthesis-of-nanodiamonds.htm

Offline Top Cat

  • PPT Invited
  • *****
  • Posts: 866
  • Province/State: Langley BC
  • Country: ca
  • Kudos: 20
Re: Ultrasonics
« Reply #1 on: November 06, 2018, 06:48:55 AM »
Interesting thanks for sharing !!!

Offline snowman18

  • Jr. Member
  • ***
  • Posts: 51
  • Province/State: BC
  • Country: ca
  • Kudos: 5
Re: Ultrasonics
« Reply #2 on: November 06, 2018, 08:35:46 AM »
Have four 100 watt 25 khz transducers with drive boards on the way, I'm looking forward to doing some experiments with black placer sand and a few other items, If these experiments fail at least I'll have one hell of a ultrasonic cleaning tank.

Offline snowman18

  • Jr. Member
  • ***
  • Posts: 51
  • Province/State: BC
  • Country: ca
  • Kudos: 5
Re: Ultrasonics
« Reply #3 on: November 06, 2018, 11:04:19 AM »
1.jpg

How to clean vinyl LP’s (records) in an Ultrasonic Cleaner

If you have a collection of old or new vinyl records, you will understand the importance of keeping them clean and dust free. Even with a budget record deck fitted with a mid-range stylus, the difference in playback quality can easily be greatly improved by cleaning your favourite LP’s. No matter how carefully you put a record away, over time dust somehow finds it’s way into the inner sleeve. And each time the record is played, this dust will damage the grooves if not removed. The question is how do you clean vinyl records safely without damaging the record surface?

2.jpg

Cleaning solutions can leave a deposit in the grooves. Even a weak soap and water solution can leave a slight covering when it dries.  A carbon fibre brush can be used before & after playing. Or a specialist cleaning cloth. But either of these record cleaning methods involve touching the record surface. A non-contact method of dust removal is by a vacuum cleaner, but that won’t clean to the very base of the record groove.

But as any self-respecting audiophile knows, the less physical contact anything has with the face of the disc, the better and most cleaning methods require some kind of rubbing or brushing. In an ideal World, the only item to touch the surface of a record should be a stylus.

However, one new method is the use of an Ultrasonic Cleaner. This ticks all the boxes with regards to non-contact with the surface of the record and they can be cleaned very thoroughly without chemicals. Microscopic dust particles are cleaned from the very bottom of the record groove.

3.jpg

What is an Ultrasonic Cleaner?

Without going into too much nerdie technical detail, Ultrasonic cleaning is achieved by producing millions of microscopic air bubbles in a tank of water, generated by a transducer that transmits the ultrasonic sound through the liquid. These tiny bubbles reach breaking point and implode giving incredible cleaning results by dislodging the build-up of dirt and grime that is normally impossible to remove by hand. The most popular use for an Ultrasonic Cleaner is for jewellery, although the range of other applications is extensive.  Ultrasonic cleaners are often used by Dentists, Vets, Tattoo studios etc, for cleaning instruments after use. Garages use them for cleaning carburettors. More on ultrasonic cleaning here.

For the best ultrasonic cleaning results with vinyl records, the water should be warm (not hot). As you can see from the photograph sent by our customer, the LP is suspended over the tank so that the faces of the disc pass through the water. It’s a little “Heath Robinson” in this case, but the principal works very well and the residue of dirt and silt in the bottom of the tank clearly shows that Ultrasonic Cleaning is one of the best ways to keep vinyl LP’s clean.

4.jpg

“I’ve just done a temporary lash-up with wood, a couple of halved rubber washers and BluTak. I’ll make something a little less flimsy in the next few days” – Robin, Hull.

5.jpg

The photo shows the deposit in the tank after cleaning 27 records. I’m really surprised there’s so much as all the records had been cleaned by a vacuum record cleaner previously”.

The machine used by Robin is a 6Ltr model which is the smallest model that has the required tank depth to be able to submerge the face of the disc under water. Also this model has a de-gassing function that gives maximum ultrasonic cleaning.

6.jpg

UPDATE (21/02/16)

I contacted the customer to ask how he was getting on with the cleaner after 1 year. Below is the reply:

“Hi Bill,

My support / spindle is still very basic but improved sufficiently for me to leave it at this (example photo attached); I’m not going to try motorising the spindle.

I usually put five records in at a time, the maximum with these separators – balsa circles with rubber ‘O’ rings glued on which protect the record labels from getting wet – soak the vinyl for quarter of an hour or more while the cleaning fluid warms up to 33 degrees centigrade and then turn the spindle one fifth of a revolution every minute for fifteen minutes on the gentler cleaning setting. Then I suck the records dry using my old vacuum record cleaning machine, without any rinsing. This process means it takes half an hour plus the soak to complete the five records. The fluid I use is L’Art du Son solution plus some Kodak Photo-flo to wet the vinyl properly.

7.jpg

The improvement over just using the vacuum cleaner is very noticeable and I am completely sold on the value of the ultrasonic tank for the listening experience. The improved sound demonstrates a remarkably thorough cleaning, far better than anything else I have experienced and it’s reassuring to be able to see the muck accumulating at the bottom of the tank. I wouldn’t be without the ultrasonic.

Thanks for your enquiry. I’m well and truly satisfied.



Offline snowman18

  • Jr. Member
  • ***
  • Posts: 51
  • Province/State: BC
  • Country: ca
  • Kudos: 5
Re: Ultrasonics
« Reply #4 on: November 06, 2018, 11:09:56 AM »
The ultrasonic cleaner used on the record cleaning project is operating at 40khz .

Offline snowman18

  • Jr. Member
  • ***
  • Posts: 51
  • Province/State: BC
  • Country: ca
  • Kudos: 5
Re: Ultrasonics
« Reply #5 on: November 06, 2018, 11:40:10 AM »
Ultrasonic pre-treatment of your placer black sand will scrub off the oxides. your flower gold now stands a much better chance of sticking to your miller table mat.

Any 40khz cleaner should work but 25khz would do a more aggressive job of scrubbing the oxides off.

Offline mcbain

  • PPT Invited
  • *****
  • Posts: 5603
  • Province/State: hope bc
  • Country: ca
  • Kudos: 116
Re: Ultrasonics
« Reply #6 on: November 06, 2018, 07:28:34 PM »
Hi.Snow man.The unit you show is very expensive.I have a smaller one that I use to clean carbs. It was 400.00.I have cleaned many things with it.I use a solution of simple green and water.Simple green is bio and does not harm the metal.The real action is the vibration,42,000 vibes a second.It is something too watch varnish just disappears in seconds.I am thinking it may remove flux and such after a melt.Now you got me thinking.Luck Mcbain.
I started out with nothing Istill have most of it.

Offline snowman18

  • Jr. Member
  • ***
  • Posts: 51
  • Province/State: BC
  • Country: ca
  • Kudos: 5
Re: Ultrasonics
« Reply #7 on: November 06, 2018, 08:02:39 PM »
Hi.Snow man.The unit you show is very expensive.I have a smaller one that I use to clean carbs. It was 400.00.I have cleaned many things with it.I use a solution of simple green and water.Simple green is bio and does not harm the metal.The real action is the vibration,42,000 vibes a second.It is something too watch varnish just disappears in seconds.I am thinking it may remove flux and such after a melt.Now you got me thinking.Luck Mcbain.

It has nothing to do with vibration, its cavitation that does the hard work, the units I purchased operate at a lower frequency than your shop unit.

The units I purchased are 100 watts at 28khz on 220 volts ac, you can purchases these to operate on 110 volts ac as well.

The 28khz frequency is more aggressive at cleaning than your 40khz cleaner, both types of transducers maybe found on tank cleaners but you're going to pay more for the 28khz unit.

A single transducer as shown below would power a one liter tank. add sodium chloride to your tap water. Simply use a good epoxy to attach the transducer.

trans.png


Offline snowman18

  • Jr. Member
  • ***
  • Posts: 51
  • Province/State: BC
  • Country: ca
  • Kudos: 5
Re: Ultrasonics
« Reply #8 on: November 08, 2018, 12:59:30 PM »
Ultrasonic Fundamentals
[/b]

The primary results of the ultrasonic treatment upon the particles in a water slurry are as follows:

    (1) the separation of particle agglomerates into independent particles, and
    (2) the production of cleaned particle surfaces.

These results are brought about by the production and collapse of many small cavitation bubbles at the liquid-solid interfaces. Cavitation bubbles are produced when sufficient ultrasonic energy is introduced into a liquid.

Due to the density change at the surfaces of solids submerged in water, attenuation the sound energy occurs at these liquid-solid interfaces promoting cavitation to take place or the surfaces of the solid particles. Also, particles which are loosely stuck together may promote cavitation near their points of contact, thereby aiding the separation of the particles from each other.

Precious Metal Recovery by Ultrasound
[/b]

A field test was run using sedimentary clays from a lake bottom containing very small amounts of precious metals. A slurry was made of these clays with water which flowed through the ultrasonic treatment unit. After treatment, the slurry was pumped into a hydrocyclone which discharged into a spiral classifier for further separation and recovery of the precious metals.

Results indicated that ultrasonic treatment doubled the recovery of the precious metals from the raw ore and enhanced the concentration of the precious metals by a factor of ten.

Offline snowman18

  • Jr. Member
  • ***
  • Posts: 51
  • Province/State: BC
  • Country: ca
  • Kudos: 5
Re: Ultrasonics
« Reply #9 on: November 08, 2018, 02:27:48 PM »
 I have now been correctly informed from a manufacture in China the best working tank thickness is 1.5mm or 2mm.

Each 100 watt generator can run one 100 watt transducer or four 25 watt transducers or even five 20 watt as long as they're wired in parallel.

For cleaning the oxides free from placer black sand it's recommended using a solvent aka cleaner. The other two experiments are top secret.

 


Gear Pan
Gold Rat