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.
Cowie Technology Corporation OCTAHEDRAL STIR 13MM L 10MM D
This item has a minimum order quantity of 134 per supplier requirements. Stirbar, octahedral, length 13 mm, diameter 10 mm
Chemglass Life Sciences Replacement Stir Bar Magnet for 50-500mL Vessels
Replacement Components for CLS-1410- and CLS-1411-Series Spinner Flasks.The Replacement Shaft consists of the glass shaft only.
Koehler Instrument Company Inc KOEHLER INSTRUMENT COMPANY INC
NC3946967 BEARING 3/16X5/16IDX2 L SLEEVE
BIG SCIENCE INC STIR BARS CROSS 5/PK
Stir Bars Length 20mm (3/4 in.) Height 8mm (5/16 in.) cross 5 pack
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.
Andwin Scientific Stir bars egg-shaped, Spinbar, 1 each
Spinbar, Stir bars egg-shaped, Designed specifically for round bottom Flasks and vessels. 19L x 9.5mm dia., For round-bottom Flasks sized 10, 25, 50 and 100mL, 1/EA
Cowie Technology Corporation DISC STIRBAR 9MM L 6MM D
This item has a minimum order quantity of 75 per supplier requirements. Stirbar, disc, length 9 mm, diameter 6 mm
Analytical Sales & Services Stir Bars 1.6X4.8MM, Parylene-Encapsulated Stainless Steel, Non-Magnetic, 1000 Units
STIR BARS 1.6X4.8MM 1000CS stir bars are engineered for precise agitation in photoredox and parallel synthesis systems. Made with durable parylene-encapsulated stainless steel, they are chemical resistant and non-magnetic, ensuring controlled mixing for sensitive applications. Packaged with 1000 units, these stir bars support high-throughput experiments, distinguishing themselves from others with their efficient manipulation by external magnetic forces.
Azzota Corp Magnetic Stirring Bar - H Type, 10mm Length, Dia. 6mm
Magnetic stirring Bar - H type, 10mm length, Dia. 6mm
Azzota Corp Magnetic Stirring Bars - H Type, 15mm Length, Dia. 7mm
Magnetic stirring Bars - H type, 15mm length, Dia. 7mm