Magnetic stirrers have found their way into a variety of different fields. However, there unparalleled practicality won’t mean much if you encounter issues. Regardless of the intended use, magnetic stirrers can be frustrating when they are not performing.
The function of a magnetic stirrer is to use a rotating magnetic field to cause a stirrer bar that is immersed within a liquid to spin and stir. When this seemingly simple task is not going as planned, there could be a few easy solutions.
Types of Magnetic Stirrers
Most stir bars are safe for heated and unheated applications. If you are having issues with your magnetic stirrer, your system may not be suited for your needs. Magnetic stirrers can be used in liquids with high viscosity. Typically, magnetic stirrers create less turbulence than other options.
Some common types of magnetic stirrers include:
- Internal control stirrers
- External control stirrers
- Single and multiple point stirrers
- Cell culture stirrers
- Industrial stirrers
One simple magnetic stirrer can perform a variety of tasks. However, depending on consistency, size, and material needs, your stirrer may not be the optimal choice for your goals. Contact an expert before you purchase to check that your stirrer best suits your needs.
Stir Bars
Your choice of stir bar can be easily changed. There are a wide variety of shapes and sizes that are commonly used in industry. The stir bar that works best for you will likely depend on the size and shape of the vessel you’re using.
Some stir bars will have a pivot ring around the center. The ring helps to reduce vibrations and wear by reducing the effects of friction from contact with the vessel. If your solution is not being thoroughly mixed, the answer may be as easy as replacing your stir bar.
Common Problems
Stirring by utilizing a generated electromagnetic rotating field is 100% wear-and maintenance-free. However, the function of your magnetic stirring system can still be inefficient or ineffective. The most common problems encountered when utilizing magnetic stirrers include:
- Insufficient mixing
- The bar is stuck
- The bar is becoming uncoupled from the magnet
If your magnetic stirrer is not working for you, it does not mean you have to replace it. The cause of these problems may have a lot to do with operating procedures. When faced with issues, the location and speed of the bar will often impact the consistency of the results.
Solutions to Common Problems
Most problems with magnetic stirring systems require simple and minor adjustments. If you are experiencing problems, you have a few solutions to consider. Depending on the setup of your stirrer, you should:
- Check the size and strength of the stir bar
- Reconsider which vessel you use
- Always position the stirrer in the middle of the vessel and plate
- Increase the stirring speed slowly at first
- Consider the volume of fluid you are stirring
When you encounter issues in your experiments, small adjustments can go a long way. It can be helpful to reread the manufacturer's instructions if you continue to have issues with the system. Proper use is always recommended and, when in doubt, reach out to 2mag for professional assistance.