It’s an age-old adage, but its message still holds true today: “You get what you pay for.” That’s a fact, whether you’re buying a car, a mattress, or a refrigerator… and it’s especially true for ultrasonic cleaners. Going cheap may save you some money in the short term, but it may actually end up costing you more money in terms of energy, detergent, and replacement parts, not to mention wasted time and energy. There are hundreds of different ultrasonic cleaning systems on the market today, made by dozens of manufacturers, and they’re all competing for your hard-earned cash. So before you lock into one particular design or manufacturer of ultrasonic cleaners based on cost, make sure you consider all of the following characteristics that can vary dramatically between makers, and see if you’re really getting a quality cleaner.
Tank Size – All things being equal, smaller capacity ultrasonic cleaners will cost less than bigger units. But depending on what you’re trying to clean, a small tank may crowd the parts and prevent the ultrasonic waves from properly penetrating the parts, leaving contamination behind and forcing you to run the unit longer. The tank must be properly sized to allow enough space around the parts for proper ultrasonic cleaning to occur.
Tank Wall Thickness – Almost all ultrasonic cleaners are made with stainless steel holding tanks, and stainless steel is expensive. Some manufacturers cut costs by reducing the thickness of the tank wall. Initially, this may not be a problem, but the high frequency vibration of the transducers will stress the stainless steel over time, and thinner gauge material may actually start to crack and leak. The stainless near the transducers is also subject to cavitation erosion, and thinner-walled tanks may develop pinhole leaks or worse quickly when this occurs.
Number of transducers – The more transducers that act on the fluid in the tank, the more complete the cleaning process. Sound waves will reach the parts from all angles, ensuring thorough cleaning of every surface. Lower-cost ultrasonic cleaners minimize the number of transducers to keep the cost down, meaning you will either have to clean the parts longer, or that the parts may not get completely cleaned at all.
Temperature control – Ultrasonic cleaning is usually faster and more thorough if the solution temperature is slightly elevated from around 110 to 150 degrees Fahrenheit. Cheaper ultrasonic cleaners might not have any sort of solution heating mechanism at all, or it may be an inexpensive controller that doesn’t maintain a constant temperature. In either case, cleaning times from batch to batch will vary dramatically as the solution heats and cools, forcing you to always run the unit longer to ensure proper cleaning. A thermostat or heater that overheats the solution may actually damage some types of parts.
Circulating Filtration System – During ultrasonic cleaning, contaminants that are removed from the parts will fall to the bottom of the tank as sludge, float around in the cleaning solution, or float on top of the solution (like oils and greases). Eventually, these contaminants will build up and affect the ability of the detergent to do its job, requiring it to be changed out. An ultrasonic cleaner with built-in circulating filtration can pass the solution through filters and remove most of the contaminants, allowing the solution to be used longer between change-outs. It isn’t absolutely necessary that ultrasonic cleaners have this feature, but it does save on the cost of detergent and the time it takes to drain, refill, and degas the new solution.
Accessories – Some ultrasonic cleaners come with added accessories that must be purchased separately if you buy a cheap system. Parts cannot be placed on the floor of the tank, so there must be some sort of basket or tray available to hold them. This is an added cost if the unit you’re considering doesn’t include one. Also, a tank cover is almost essential to keep dust and dirt out of the solution when it’s not in use. If your new, inexpensive ultrasonic cleaner comes without a cover, you’ll have to shell out for that separately as well.
You don’t have to buy the most expensive cleaner on the market to get one that does a great job cleaning your parts. The type of parts, quantity of parts, types of contaminants, and expected usage all factor into choosing the right system. Be sure you know what you’re paying for before you lay down your money, or you may be sorely disappointed.