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.
Chemglass Life Sciences Stir Bar, Magnetic, Egg-shaped, fits 300mL-500mL flask, Length x Dia. in inches: 1 1/2 x 5/8
Stir Bar, Magnetic, Egg-shaped, fits 300mL-500mL flask, Length x Dia. in inches: 1 1/2 x 5/8. Egg-shaped magnetic stirring bar provides its own pivot point without separate ring or abrupt change in contour. Designed for use in round bottom vessels, it is shaped to spin freely, unrestricted by the vessel contour. Manufactured with FDA-grade and USP Class VI PTFE.SEE CG-2005-20 FOR STIR BAR KIT
Chemglass Life Sciences Stir Bar, Magnetic, Egg-shaped, fits 500mL-1000mL flask, Length x Dia. in inches: 1 5/8 x 3/4
Stir Bar, Magnetic, Egg-shaped, fits 500mL-1000mL flask, Length x Dia. in inches: 1 5/8 x 3/4. Egg-shaped magnetic stirring bar provides its own pivot point without separate ring or abrupt change in contour. Designed for use in round bottom vessels, it is shaped to spin freely, unrestricted by the vessel contour. Manufactured with FDA-grade and USP Class VI PTFE.SEE CG-2005-20 FOR STIR BAR KIT
Research Products International Corp Flea Micro Magnetic Stirring Bar, 10 x 3 mm
Micro (Flea) magnetic stirring bars are designed for stirring small volumes in vessels such as vials, tubes and gradient makers. Particularly useful for environmental testing and life science applications in which small sample volumes need to be prepared and evaluated.
Chemglass Life Sciences Stir Bar Dual Purpose Positioner/Retriever, Polyethylene, 5/8" Diameter X 12" OAL
Stir Bar Dual Purpose Positioner/Retriever, Polyethylene, 5/8" Diameter X 12" OAL. Convenient dual purpose polyethylene unit permits positioning of the spinbar at the bottom of a vessel without dropping bar into liquid. Also allows bar to be removed without touching or pouring out liquid. Retriever slides within outer casing. To pick up spinbar, slide retriever down; to release bar, slide retriever up. 5/8in in diameter and 12in overall length.
Electron Microscopy Sciences Veco Parallel Bar w/ Divider Handle R100D, Nickel
Veco Grids offer superior handling characteristics. Plus, with a 0.8 mil thickness, Veco Grids are the most rigid grids available. 3.05 mm diameter and 0.8 mil thickness.
Material: Nickel
Pitch: 250 µm
Hole: 200 µm
Bar: 50 µm
Electron Microscopy Sciences Veco Parallel Bar with Divider R100Aspec, Nickel
Veco Grids offer superior handling characteristics. Plus, with a 0.8 mil thickness, Veco Grids are the most rigid grids available. 3.05 mm diameter.
Material: Nickel
Pitch: 250 µm
Hole: 200 µm
Bar: 50 µm
Electron Microscopy Sciences Veco Parallel Bar with Handle Grid R300, Copper
Veco Grids offer superior handling characteristics. Plus, with a 0.8 mil thickness, Veco Grids are the most rigid grids available. 3.05 mm diameter.
Material: Copper
Pitch: 85 µm
Hole: 45 µm
Bar: 38 µm
Electron Microscopy Sciences Spinbar Circulus™ Dumbbell Stiriing Bar 52mm Yellow
These magnet stirring bars provide strong turbulence at relatively low speeds, offering reduced surface contact and excellent centering characteristics, particularly in vessels with convex bottoms. Ideal for 'problem' liquids, highly viscous mixtures and metal particles in fluid. All sizes have solid PTFE end disks 20 mm (.79”) in diameter. Bar diameter is 8 mm (.315”).
Color: Yellow
Electron Microscopy Sciences Spinbar Circulus™ Dumbbell Stiriing Bar 52mm Blue
These magnet stirring bars provide strong turbulence at relatively low speeds, offering reduced surface contact and excellent centering characteristics, particularly in vessels with convex bottoms. Ideal for 'problem' liquids, highly viscous mixtures and metal particles in fluid. All sizes have solid PTFE end disks 20 mm (.79”) in diameter. Bar diameter is 8 mm (.315”).
Color: Blue