Stirring Bars and Rods
Products of various sizes, shapes, and material compositions designed to aid in manual or automatic stirring of laboratory solutions. Includes glass stirring rods, magnetic stir bars, and stir bar retrievers.
What Is a Magnetic Stir Bar?
Magnetic stir bars are stirrers or stirring hotplates used with magnets to mix a liquid or solution by creating a vortex.
A number of factors affect magnetic stir bar efficiency and effectiveness, including its size, shape, and material. Sizes (L x Diameter) range from 2 x 2 mm to 159 x 27 mm and shapes include:
- Polygonal or octagonal magnetic stir bars are the most common shapes; the multiple surfaces add turbulence to the mixing action
- Elliptical or egg-shapped stir bars work especially well with round-bottom flasks
- Wedge-shaped spin bars produce more significant turbulence for dissolving salts or in samples containing sediment
- Spin bars with fins or vanes, designed for smaller vessels, tubes, or cuvettes
- Micro (“flea”) stir bars for mixing extremely small samples
What Kind of Magnet Is Used?
Stir bar magnets are typically made from Alnico, a combination of aluminum and nickel. They may also be made from Samarium cobalt, a rare earth metal that produces the stronger magnetic force needed to mix very viscous substances.
Stir bar magnets are usually encapsulated in white or colored PTFE, hard plastic, or borosilicate glass, and coatings may meet FDA grade or USP requirements. PTFE is durable, inert, and can be autoclaved. Glass-encased cylindrical magnets are useful for high-temperature applications.
How Does It Work?
During the stirring process, integral or removable pivot rings on the stir bar reduce contact with the vessel to help avoid marring plastic surfaces. Some round stir bars have slightly raised ends that create a de facto pivot point, while others have more pronounced round centers that help to keep them in motion. Stir bars may be reusable or disposable.
Magnetic stir bars may be sold individually or in magnetic stir bar kits that include multiple bars in a range of sizes.
World Precision Instrument Glass Rod-GR100-6
1.0 mm diameter glass rods are perfect for making tools, probes, and tips.
Foxx Life Sciences Borosil® Reusable Solid Stirring Rods, Polished Glass Stirrers, 7mm x 305mm (Extra Length), 20/CS
Borosil® Polished Glass Solid Stirring Rods are constructed from smooth, low-expansion, low-extractable borosilicate glass. Their mechanical strength, excellent heat resistance, and outstanding chemical compatibility make them the perfect general use stirrer. Borosil® Glass Stirrers are avaialble in two widths: 7mm and Extra-Wide 9mm. Each width is available in four lengths, from the Short 150mm to the Extra Large 305mm. In collaboration with Borosil Glass Works, Foxx Life Sciences is proud to bring the outstanding quality of Borosil® Type 3.3 Borosilicate glassware to North America for the first time. Manufactured from the same USP Type 1 borosilicate glass that North American scientists have come to trust, Borosil® Laboratory Glassware offers unparalleled mechanical strength, clarity, and reliability at competitive prices. And thanks to a unique annealing process, Borosil® Glassware is stress-free and incredibly resistant to thermal shock.
Hach Company Stir Bar Retriever
Polyethylene pickup rod with powerful magnet sealed in one end and hangup grip on other; 31 cm (12") long.
MSC Mag-Mate Lift Magnet, 250 lb Capacity, Permanent, On/Off Handle, 2 Poles
This permanent lift magnet offers a 250 lb capacity for handling flat objects. It features an On/Off handle for activation and has two poles, making it suitable for various lifting applications.
- Permanent magnet type
- On/off handle for easy activation
- Maximum load capacity of 250 lb
- Two poles for effective lifting
- Includes a 3 inch ceramic magnetic retriever
- Designed for use with flat objects
- Overall length: 5 inch
- Overall width: 2.63 inch
- Overall height: 2.625 inch
MSC Industrial Magnetics, Inc. Lift Magnet, 220 lb Capacity, Permanent
This permanent magnet lift is designed for lifting round and curved surfaces such as shafts, thick-walled pipe, or billet, with the ability to also handle flat materials. It features specially designed pole shoes that provide a deep penetrating magnetic field and part stability, offering a 220 lb working load limit.
- On/off rare earth permanent magnet
- Handle requires only 90 degree rotation and locks at both on/off positions
- Durable, recessed metal nameplates
- Corrosion-resistant, plated magnet surface
- Heat resistant up to 180°F (82°C)
- 3:1 design factor
- Meets ASME B30.20 BTH-1 Design Category B, Service Class 3
Electron Microscopy Sciences 12" Polypropylene Retriever
Polypropylene stirring bar retrievers are ideal for use with all stirring bars. The entire retriever is totally encased in a chemically resistant polypropylene, with a handy ring for hanging when not in use.
Electron Microscopy Sciences 18" Polypropylene Retriever
Polypropylene stirring bar retrievers are ideal for use with all stirring bars. The entire retriever is totally encased in a chemically resistant polypropylene, with a handy ring for hanging when not in use.