Restore antique locks with an ultrasonic cleaner

According to one source the earliest known lock dates to the ruins of the Khorsabad palace near Nineveh and is estimated to be 4,000 years old.  Much more common are the padlocks and door locks made over the past 200 years or so and sought by collectors. If collectors wish to remove grime and rust from their locks while maintaining an antique patina, a short immersion in an ultrasonic cleaner should yield satisfactory results. 

Cleaning Locks with an Ultrasonic Cleaner

The advantage of using an ultrasonic cleaner for lock restoration is that the cavitation action doing the cleaning does not damage the surface of the locks or their mechanisms.  Such is not the case if collectors resort to steel wool, wire brushes and solvents that can scratch the surfaces.  Moreover, the cavitation action penetrates openings in the mechanisms and can remove hardened grease and other compounds impossible to reach by hand scrubbing.

For the serious lock collector – or for one who restores locks for others – an ideal piece of equipment is an Elmasonic E ultrasonic cleaning unit available from Tovatech.  They are offered with tank capacities ranging from ½ to 7-½ gallons and can be used for cleaning a wide variety of equipment that can be safely wetted in a biodegradable ultrasonic cleaning solution.

Regardless of size the cleaning process works the same.  Generator-powered ultrasonic transducers bonded to the ultrasonic cleaner’s tank operate at an ultrasonic frequency of 37,000 cycles per second (37 kHz) to create billions of tiny bubbles in the cleaning solution.  These implode with tremendous force on contact with the lock’s surfaces, quickly and safely blasting away rust particles, grime, grease and other contaminants from brass, copper, cast iron and steel surfaces leaving a clean smooth finish.  The units are equipped with what is called a “Sweep” function meaning that cavitation action is distributed evenly throughout the bath, avoiding what are called “standing waves” that can cause streaking on softer metals such as brass keyhole covers.

Setting up your Ultrasonic Cleaning Operation

Place the tabletop Elma ultrasonic cleaner on a level surface near a standard 115-volt GFI outlet.  Prepare the ultrasonic cleaning solution per the manufacturer’s directions.  We recommend elma tec clean A4 diluted to 2-5% with water.  This is a universal cleaner for surfaces made of metal, glass, ceramics, plastics and rubber to remove oil, grease, combustion residues, soot and other organic contamination.

Add the solution to the tank’s fill line and operate the unit without a load until cavitation-inhibiting trapped air bubbles no longer come to the surface.  This step, called degassing, must be done each time you prepare a fresh cleaning solution.

When you are ready to clean, set the unit’s thermostat to 50˚- 80˚C.  Ultrasonic action will begin when the set temperature is reached (or you can start it manually).  The amount of time in the bath is determined by the condition of the lock, but start with setting the timer for 5 minutes.

Place the locks in the cleaning basket (they should not contact each other) then lower them into the solution and put the plastic cover in position.  At the end of the cleaning cycle remove the basket and inspect the locks then rinse in fresh water and allow them to dry.

Added protection for parts made of steel or iron can be achieved by adding 0.1% of elma-KS to the cleaning bath or during rinsing.  This provides a coating on a molecular level to protect temporarily from corrosion.

Maintaining your Ultrasonic Cleaner

After repeated use the bath will become dirty and cleaning time will get longer.  Drain the tank and dispose of the spent solution according to local regulations.  Clean the tank according to the instruction manual then refill it with a fresh cleaning solution.

As you become proficient you’ll think of other jobs that can be performed by your ultrasonic cleaner and perhaps turn a hobby into a business.

Contact the ultrasonic cleaning experts at Tovatech for information on cleaners and the various types of cleaning solutions that can be used for specific cleaning tasks.