how to degas your ultrasonic cleaner

Why Degas Your Ultrasonic?

Before the start of each working day it is best to degas the liquid in your ultrasonic cleaner tank.  This simple procedure allows the ultrasonic cleaner to work most effectively, since the ultrasonic waves can pass more freely through liquid than they do when air is mixed in the liquid in the tank.  If you are in a lab, or a dental, vet or medical practice this is the ideal time to prepare for your daily foil test.

You should also perform this task whenever you start with a fresh tank of water during the working day.  NB Take extra care when you empty your ultrasonic cleaner tank, as this is a risky time – see notes below.

Unless you are in a laboratory or clinical setting, where you will be completing a foil test to meet regulatory obligations, you can use the degas process to start your daily cleaning.  The first 10 minutes of degas/cleaning will be a little less effective than the rest of the day, but they will still generate a very good cleaning result.  Anyway, you’re paying for the electricity – you may as well get some value out of it.

How to Do It

  1. Fill the tank with the recommended amount of water and add a squirt of dishwashing detergent.  The detergent will help to soften the water which assists in the degas process.
  2. Degas the water in the tank.  Set heater thermostat to 60C.  After temperature is achieved run unit on cleaning cycle for about 10 minutes.  Degasing will expel the air so that the unit operates at optimum effectiveness.
    • NB If your machine does not have a heater, or if the heater is slow to increase temperature, you can boil water in a kettle to get the same result.  In a boil proof jug add two parts boiling water  to one part tap water.  If the tap water is room temperature (25C), the combined water will give you about 60C.  Adjust the mix for local conditions.


  1. Foil Test. Always degas the tank before doing a foil test.
  2. Many desktop machines are designed to maintain minimum set temperature with their heater, but they can be rather slow to heat up, especially if ambient (or tap water) temperature is low. You can run the machine (e.g. start to clean some items) while the unit is heating.  This will usually only draw a small amount of additional electricity, but it will save time and help to get the tank up to operating temperature a lot quicker.  Covering the tank with its lid will also help speed the process.
  3. Empty Tank Safely. Some hints to safely empty liquid from your ultrasonic cleaner’s tank, for units without a tap.
    1. Water and Electricity Do Not Mix. Turn off power and disconnect unit from mains before emptying tank. Refill tank when unit back in designated safe working location and before power is reconnected to machine.  Remove all spills promptly and completely, ensuring that no water is on or near leads, plugs or power points.  Do not turn power back on until it is safe to do so.
    2. Cool Tank to 25C. Wait until liquid inside tank has cooled before emptying – you should turn heater off, or set thermostat to zero C and empty liquid only when contents has dropped to room temperature.  This will prevent damage to heater pad.
    3. Check for Lost Stones.  If you have been cleaning jewellery check that no stones have not come adrift from settings BEFORE you empty the tank. This problem is more common than you might think.  If you discover a setting is minus a stone use our procedure to find it in the tank, or ensure that you pass liquid through a fine sieve. Do not just pour liquid down the drain.
    4. Avoid Splashbacks.  Most ultrasonic cleaners are very well sealed around the top and sides of the unit.  But bench top ultrasonic cleaners will commonly have holes in the base or rear to allow for venting of excess heat from the unit.  So it is possible for liquid to enter the unit when tank is being emptied.  You would be amazed at where splashed water can end up. We recommend against vigorously upturning the unit to empty the tank, as this can cause unwanted liquid splash backs or internal components becoming dislodged.   Instead, use a household plastic jug to bail the liquid out (also makes it easier to use a sieve if searching for missing stones) and to wipe out the last bit of liquid in the tank with a clean sponge.  This procedure takes no more than a few seconds, but it can save a lot of time and money.

Liquid Glass Oz designs quality ultrasonic cleaners for commercial operations in Australia and New Zealand (N18973)

Cleaning Fired Brass Cartridge Cases

Are you a recreational shooter who wants to reuse his fired dirty cartridge cases?

Whether you want to save money or just get the satisfaction of repacking your own ammo, you know that you have to make those cartridges perfectly clean for an accurate firing result.

Over the years shooters have used a variety of methods to try to get their cases back to that straight out of the box look.  Enthusiasts have tried tumblers, electric drills and all sorts of caustic concoctions. More recently, the move to ultrasonic cleaners has gained momentum.

Ultrasonic cleaners have a number of advantages over these other brass cleaning methods:

  • Low operating costs  – electricity cost for ten hours operation is only about 25 cents
  • Kind to the environment – do we really need any more toxic chemicals around us when we’re cleaning, and where do we put them when the cleaning is done?
  • Simple to use
  • Clean and relatively quiet (just try talking anywhere near a vibratory tumbler)
  • Quick, yet thorough, and most importantly
  • Safe – certainly perfectly safe, compared to the hazards to your fingers and hands from cleaning with an electric drill and wire brush!

Using ultrasonic cleaners, shooters have cleaned, restored and reused cartridges that have been fired four, five, six, or even more times.  And what´s more, shooters claim these carts are as good as new.  We have seen the results ourselves and have no doubt that the claims are true.  So, what’s the procedure?

Step 1 Gather the Ingredients and Tools

You’ll need the following items:

  • an ultrasonic cleaner (preferably 100 Watts power, but machines of 50 Watts will still do an acceptable job, if a bit slower to get there)
  • vinegar solution (half water/vinegar)
  • dishwashing detergent (any brand, but we use Morning Fresh – only a squirt will do)
  • Pyrex or glass beakers x 2
  • baking soda – you need to neutralise the acid in the vinegar after cleaning – this is important.  If you skip this step you may start to de zinc the brass.
  • distilled water – to rinse the cases off, so they can dry without marks or deterioration from the chemicals in the tap water
  • hair dryer/oven (not microwave)
  • your already fired cartridge cases, of course.

Step 2 Setting Up

Detailed instructions for setting up your ultrasonic cleaner are available if required.

  • Put aside your fired cartridge cases.
  • Set up your ultrasonic cleaner in a safe place, well away from traffic areas.  Many shooters already use a shed or workshop away from the living zone of the house (legacy of the noisy tumbler).  This is a good place to stay, especially if you want to keep this gear away from children.
  • Fill cleaning tank to about 2/3 level with normal tap water and insert the cleaning basket and just a single drop of dishwashing liquid.  Into the beaker pour the vinegar solution plus a tiny drop of dishwashing detergent, up to about 2/3 level – you will need to leave space for the cases that you will put in later (obviously the cases will displace the vinegar solution).  Don’t worry. The ultrasonic waves will pass unimpeded from the tank water, through the beaker, and to the cartridge cases to perform the cleaning you desire.
  • Place beaker inside the tank basket, making sure you top up the water level in the tank to the MIN water level mark.   Damage to the unit’s heater pad can occur if you allow the water level to drop too far. NB Many units will show the recommended MIN liquid level for safe operation.

Step 3 Doing the Cleaning 

  • Degas.   You want to make the cleaner run as effectively as it can.  This occurs when the tank is at the correct temperature and when the air has been removed from the liquid medium.  If your ultrasonic is heated, set the temperature at 60C.  If your tank is not heated follow the instructions in our blog.  Then run the cleaner through a normal cycle of between 5 and 10 minutes. The dissolved air should now be purged from the tank, so the ultrasonic effect can clean as well as possible.
  • Cleaning Cycle 1.  Add your fired cases to the beaker – carefully, since the tank will be hot.  Run the unit through a full cleaning cycle (10 – 15 mins). NB While the cleaning cycle is on prepare the 2nd beaker. Add 1 tsp baking soda to 2/3 beaker of tap water and mix well.
  • Cleaning Cycle 2. Carefully remove the beaker from the tank and rinse the cases under running water (preferably using a metal sieve).  Note improvement in appearance of the cases before adding cases to the 2nd beaker, as ultrasonic cleaners do vary in power. You may sometimes need to return the cases to the beaker, for an additional run through the vinegar/detergent solution.  If you are satisfied with cleaning progress, add the cases to 2nd beaker and place inside basket. Run ultrasonic an additional 10 – 15 mins cycle. Remove the cleaned cases from the beaker and rinse under tap.  At this stage cases will usually be clean enough to repack.  If any residual contamination  is present (unlikely, but remotely possible) then return cases to the beaker, with tap water and run ultrasonic a further 10 mins. Make sure you turn the machine OFF as soon as the cleaning is complete and reset the thermostat on the heater to zero C.  This could save the cost of expensive repairs to your heater, or even the ultrasonic transducers, if the liquid level is allowed to drop too far.
  • Distilled Water Soak.  Soak cleaned cases in beaker for 15 mins.

Step 4 The Moment of Truth

Remove cases from beaker and strain with a sieve.  They are now clean and just need to be dried for reuse.  Shooters commonly use a hair dryer, conventional oven or a drying rack to dry the cases completely.  Your environment and circumstances will dictate what is best for you.

  • A drying rack is fine if the weather is warm, but even under ideal conditions it may take a couple of days for the cases to be completely dry.
  • Oven drying is a great way to dry quantities of cases, and it is quick.  You should be able to completely dry several trays of cases in 45 minutes at 100C.  Just avoid trying this in a microwave oven.
  • Hair Dryer works well, especially for small batches, but a bit fiddly for serious quantities.
  1. You can streamline the process by using Cleaning Cycle 1 as your degas step.  This first cycle won’t be quite as effective as later, but it will still be very good.  Anyway, you are paying for the electricity – you may as well put it to use.
  2. Cleaning cycle times are estimates only.  How many cartridge cases you can clean in a given timeframe will vary from machine to machine.  It depends on tank capacity, power (wattage) of the unit, and of course, the size of the cases (the more volume per case the slower cleaning will be).  The more powerful the unit the more cases it will clean at the same time, but of course, the tank has to be big enough to hold them.  If you overload a machine with dirty cases you will quickly notice a change in the sound of the cleaner in operation (it will sound ‘dead’ as it becomes overloaded).  As an experiment, try running your ultrasonic with just plain water, then listen for the difference in sound when you add a large rock or house brick.
  3. Typically, the power of an ultrasonic cleaner increases in proportion to its tank capacity.  However, you can sometimes find a large unit which is quite under powered.  A tank of 2L capacity will appear underpowered with a 50 Watt transducer.  At 2.5L we recommend 100 Watts, and over 3.5L 150 Watts.
  4. The smaller type of plastic ultrasonic cleaner can still clean cartridge cases effectively.  However, these units are generally designed to have a break between cleaning cycles, otherwise the transducer could be overtaxed and fail.  You can still use them, but you need to recognise their limitations.  Follow the user instructions and your machine will last longer.
  5. The procedure provided in this blog has been tested by shooters in Australia under normal Australian conditions.  The products required to perform the cleaning process are readily available and cheap.  They are also safe to operator and the environment.
  6. If you have bought a new machine to clean your fired cart cases we recommend you test it first.  Click here for our blog on testing the function of an ultrasonic cleaner.  NB We strongly recommend the use of a surge protector to prevent power spikes damaging your ultrasonic cleaner.
  7. Just to recap – don’t forget to add baking soda as per procedure.  De zincing of your brass looks ugly and might even be dangerous when you shoot.  Take care of your gear.
Liquid Glass Oz designs quality ultrasonic cleaners for commercial operations in Australia and New Zealand (N18973)

Testing Your Ultrasonic Works

Not sure that your ultrasonic is working properly?

The foil test is one test that can tell you if  it is.

Foil Test

The foil test is commonly used in medical, vet and dental practices, before the start of each day.  It is critical that surgical instruments are properly cleaned, then sterilised.  A properly functioning ultrasonic cleaner is the key to an effective cleaning process.


  1. Fill the tank with the recommended amount of water and add a squirt of dishwashing detergent.  Detergent will help to soften the water.
  2. Degas the water in the tank.  Set heater thermostat to 60C.  After temperature is achieved run unit on cleaning cycle for about 10 minutes.  Degassing will expel the air so that the unit operates at optimum level.
    • NB If your machine does not have a heater you can boil water in a kettle to get the same result.  In a boil proof jug add two parts boiling water  to one part tap water.  If the tap water is room temperature (25C), the combined water will give you about 60C.  Adjust the mix for your local conditions.

Test Procedure

You will need a piece of kitchen aluminium foil large enough to cross the tank diagonally and to drop towards (but not quite to) the bottom of the tank, with some excess foil above the water, that you can hold onto.   The foil should be oriented vertically (ie hanging downwards) – if it is laid horizontal the test will be invalid. NB Do not allow body parts to touch or be immersed in the tank water at any time during cleaning operation.

passed foil test

Typical Result – 90 seconds in 100W Ultrasonic Cleaner

Run ultrasonic cleaner through a 10 minute cycle, while holding the foil above the water line, with the foil descending to just above the bottom of the tank, and hanging diagonally across the tank.

Remove and inspect foil.  A functioning ultrasonic cleaner will show evidence of the cavitation effect on the foil.  The more powerful the machine the more intense the reaction.  This may range from pin sized indentations in a light weight machine of say 30W, to foil being ripped to shreds in a larger unit (say 100W+).  Lack of indentations is a sure sign that machine is not working properly.  If you performed this test after delivery from the supplier you should advise the supplier and request return/replacement instructions.

Warning:  Some cheaper machines are named in a way that will deliberately mislead the buyer.  Unless the machine clearly states that it is an ultrasonic cleaner  customers should assume that it is not.   Ultrasonic cleaning pretenders will never pass the foil test.  Contact the supplier or your local Department of Fair Trading for further advice.

NB If you are in a medical/dental practice consult your practice manager or your practice procedure manual. Medical practices in Australia should refer to AGPAL if they need specific guidance.

Liquid Glass Oz designs quality ultrasonic cleaners for commercial operations in Australia and New Zealand (N18973)

Setting Up Your Ultrasonic Cleaner

OK.  You’ve bought your new ultrasonic cleaner and you want to know how to set it up.  There’s a trick to doing most things – and this is no exception.  A little time spent following a procedure could save you a lot of money!

Protecting Your Investment

Inspect the box for damage before opening it.  If outside shows any sign of rough treatment during transport, take photos – they might be needed to show the supplier or freight company for a claim.

  1. Take more photos of the unit and anything inside the box if they have been damaged in transit.  Take a clear image of the unit’s serial number.
  2. Inspect contents. Take particular note of the tax invoice and the unit’s user manual/operations guide.  Often the items supplied will be specified in the user manual.  Check you have them all.  If not, contact the supplier ASAP and ask for anything that seems to be missing.
  3. Tax Invoice  A valid tax invoice will show GST included in the sale, the supplier’s Australian Business Number (ABN) and address in Australia.  The tax invoice is a valuable document which should be kept safe and produced (or copied) if you ever have any warranty issues.   Some sellers on Ebay will provide a tax invoice which is generated through their system.  As long as the document meets the requirements set out in the New Tax System (GST legislation) it doesn’t matter what it looks like.  This contrasts with invoices/shipping documents that make no mention of the words tax invoice, GST included in the purchase and the supplier’s ABN.  We recommend caution if dealing with a supplier who ships cleaners without a valid tax invoice, because it is extremely unlikely that you are dealing with a registered Australian business who can be forced to adhere to Australian consumer protection laws.

Product Safety and Compliance

Once you know you have everything that’s supposed to be included, you can move on further.  The next step is about checking your unit is safe for you and your staff.

  1. Check the power lead provided with the unit has an approved Australian/New Zealand style plug – sometimes suppliers will provide one that fits in the socket, but it does not have the insulation on the top pins (normally black).  Plugs without visible insulation on the top two pins are the ‘old style’ which ceased being approved for sale in the late 1990s.
  2. Check for C Tick label.  Electrical equipment needs a C Tick label to identify the authorised supplier and to show that the supplier can prove the device meets Australian/NZ EMC requirements.  By law ALL ultrasonic cleaners sold in Australia and New Zealand must have this label, whether imported or manufactured locally.  They also require the supplier’s electrical code (usually a number starting with letter N or V, representing the state the company is registered in).   NB If the unit does not have a C Tick and the supplier’s electrical code, then it is illegal for sale in Australia and New Zealand and it may also be unsafe.  Contact your local Department of Fair Trading and request a refund from the supplier.
  3. Check power supply.  Most quality units will be manufactured for 240Volt mains supply.   Many units will state 220 or 230 Volts, or some range between these.  The closer to 240 Volts the better.   If the unit is labelled less than 220 Volts its working life can be much less than one made for 240.  NB Do NOT attempt to use a device made for US power supply (110 Volts).  Return it f or replacement or refund.
  4. Use a surge protector. Even robust commercial ultrasonic cleaners can fail due to power surges.  Like computers, these days, ultrasonic cleaners all have electronic components which can easily burn out when power spikes occur.  We recommend taking sensible precautions, like using a quality surge protector at all times and to remove the device from the power outlet during electrical storms,  or when you are absent from the workplace..

User/Operating Manual

Most suppliers will provide a user or operating manual.  Manuals from quality suppliers units will be in plain English that the average person can understand.  Often the manual will also specify the unit’s warranty and support arrangements.   We recommend against items that must be sent overseas for warranty service.  The following points are obvious, but we’ve all seen the line – if all else fails read the manual.

  1. BEFORE you connect the unit to the power supply, or attempting to use it ensure that you read the manual and understand it.
  2. Follow the instructions in the manual.  If you don’t, often the manufacturer’s warranty will not apply.  It could be an expensive mistake.

Next Step

After you have set up your machine as per supplier’s user manual, you should immediately test its function.   Run a simple foil test to satisfy yourself you have a true ultrasonic cleaner, not a dud.  If the machine fails the test contact the supplier and have it replaced/get a credit.


  1. EMC is Electro Magnetic Compatibility. When a product shows the C Tick symbol it tells the consumer that the supplier has proven that the device meets the Australian/New Zealand regulations for EMC.  A product that does not meet EMC rules may interfere with radio and other communications, including devices such as pace makers and other sensitive life saving equipment.
  2. The supplier’s code (usually a number starting with letter N or V) on an electrical product tells the consumer that the supplier has tested the device for compliance with the Australian/New Zealand regulations for electrical safety.  The CE label often seen on electrical products has not value in Australian/NZ.  It is easily confused with an almost identical CE label which represents Chinese Export.
Liquid Glass Oz designs quality ultrasonic cleaners for commercial operations in Australia and New Zealand (N18973)