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.
V&P Scientific Inc STIR ELEMENT, CYLINDER, Stainless Steel, Passivated, Used in Microplates, Tubes/Vials, 200/pack
STIR ELEMENT, CYLINDER, Stainless Steel, Passivated, 1.9mm Diameter, 4.8mm Length, 600°C Max Operating Temp
Azzota Corp Magnetic Stirring Bars - Z Type, 7mm Length, Dia. 3mm
Magnetic stirring Bars - Z type, 7mm length, Dia. 3mm
Azzota Corp Magnetic Stirring Bars - Z Type, 20mm Length, Dia. 6mm
Magnetic stirring Bars - Z type, 20mm length, Dia. 6mm
Research Products International Corp MAG-NET Magnetic Spin Bar Remover/Restrainer
MAG-NET allows removal of spin bar from any beaker without touching the solution. Simply place MAG-NET against side of beaker and slide upwards. Conveniently hold spin bar in place while pouring solution from beaker. Safer and more convenient than immersion style retrievers. Heavy duty magnet is encased in polypropylene for easy cleaning and autoclaving.
Chemglass Life Sciences Plain PTFE Magnetic Stirring Bar, 50 x 8 mm, for Magnetic Stirrers
Plain PTFE-coated magnetic stirring bar (50 x 8 mm) for general-purpose laboratory mixing on magnetic stir plates. Its cylindrical plain profile provides effective agitation and produces increased turbulence at low speeds, while the PTFE coating offers chemical resistance and a non-stick surface.
- Plain cylindrical shape for general-purpose stirring.
- Dimensions: 50 x 8 mm.
- PTFE coating provides chemical resistance and non-stick surface.
- Produces increased turbulence at low stirrer speeds.
- Compatible with standard magnetic stir plates and laboratory mixers.
- Sold individually for easy replacement.
V&P Scientific Inc STIR ELEMENT, DISC, NdFeB Magnet, 42MGO, PVDF Encapsulated, Used in Microplates, Syringes, Tubes/Vials, 10/pack
STIR ELEMENT, DISC, NdFeB Magnet, 42MGO, PVDF Encapsulated, 8.0mm Diameter, 1.8mm Height, 150°C Max Operating Temp for Magnets
Hach Company Stir Bar, Magnetic, Plus Shape, 3/4"
This magnetic stir bar adds speed and efficiency to your mixing requirements. The “+” shape creates a deep vortex and provides stable, quiet operation.
Sigma Aldrich Fine Chemicals Biosciences CORNING MAG STIR BAR RETRIEVER
NC3848688 CORNING MAG STIR BAR RETRIEVER