The Difference Between a Lab Shaker, Rocker and Rotator

The Difference Between a Lab Shaker, Rocker and Rotator

When speaking with researchers about lab equipment, it is not uncommon to hear “I wanted a rocker and I got a shaker,” or even the reverse, “I wanted a shaker and I got a rocker!”

It is common for these terms to be confused. They seem to vary by region, such as those who refer to a carbonated cola beverage as “pop” or “soda.” Manufacturers also use the terms somewhat interchangeably. Below, we’ve included a few simple diagrams to help explain the difference between these products, along with a list of questions to help you find the best equipment for your scientific research needs.

A Guide to Selecting the Best Shaker or Rocker for Your Laboratory:

Rockers

A rocker, like the MIDSCI product pictured below, moves back and forth like a rocking chair. This model can be used for a broad range of mixing applications. 

Pictured Below: MIDSCI Variable Speed 2D Rocker, Shop PR1MA™ Rocker

Shakers

Moving in a horizontal circular motion, shakers are designed for thorough mixing of any vessel. 

Pictured Below: MIDSCI Orbital Shaker, Shop Orbital Shaker

Rotators

The most distinguishing feature of a rotator is its end-over-end motion, which may be vertical mixing, horizontal mixing, or both.  

Pictured Below: MIDSCI Roto-Mini Series, Shop Roto-Mini Series

3-D Models

You may also hear these products referred to as Belly Dancers^TM, Nutating Mixers or Gyro Twisters. These provide a unique undulating motion, that some scientists prefer to a rocker or shaker. 

Pictured Below: Benchmark BenchWaver 3-D Rocker,  Shop BenchWaver 3-D Rocker

5 Questions to Help Assess Your Mixing Equipment Needs

Once you know which mixing product you are looking for, it is much easier to get what you want AND need. Use these five questions as a guide during the purchasing process:

1. “Will I need materials to be heated or cooled?”
   There are a wide variety of units that come with heating and refrigeration capabilities.
    
2. “How big of a platform do I need?”
   Choose from products with single and stacking platforms or a variety of platform sizes. Before ordering, it is helpful to lay out the maximum supply of materials you would shake at one time and measure the occupied space. This can help ensure you don’t order a platform that is too small or one that takes up half the bench to rock one Western blot. Many units also have holders, clamps and/or racks for a variety of vessels.
    
3. “What is my max RPM?”
   RPM stands for rotations per minute. Not sure if you need capability for 60 RPM or 300 RPM? Think of tracing the outside of a dinner plate with your finger. A unit with 60 RPM moves at a speed comparable to tracing the outside of the plate in one second, or 60 rotations in one minute. At 300 RPM, the speed is comparable to completing five rotations around the dinner plate in one second.
    
4. “Will I need the unit to be compatible in any environment other than normal bench life?”
   Be careful moving your equipment into different environments. A CO₂ incubator will destroy a normal bench shaker — instead, look for something that is meant to be put in a CO₂ incubator.  Cold rooms and general incubators can also shorten the unit’s life, unless they can acclimate. And with some units you will void the warranty if it’s used anywhere besides the bench. If the unit is to be used in a unique environment, read the specs or ask your supplier. 
    
5. “What works best for the applications I will be performing?”
   After speed and temperature, your protocol will help determine the product best-suited for the job. For example, if you are doing Western Blots, many labs that will argue a rocker is better than a shaker or a shaker is better than a rocker.

MIDSCI Can Help You Shake, Rattle and Roll with the Right Motion Equipment

Save time and frustration by ordering your laboratory equipment with MIDSCI. We are large enough to deliver and small enough to care, for a wide range of equipment that controls motion and temperature. We help scientific researchers find the best equipment — including shakers, stirrers, rockers, rotators and much more. And we’ve got the customer service team you need to feel confident in your purchase. 

Submit a request online, call us toll-free at 1 (800) 227-9997 or send an email to tech@midsci.com.