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.
Electron Microscopy Sciences 5 Spinplus Spin Bar Assortment Box
Add speed and efficiency to your mixing, the "+" shape creates a deep vortex and provides stability to your mixing, 5 SpinPlus magnetic stirring bars, PTFE, consists of 1 each: 3/8"x3/8", 3/4"x 3/4", 1"x1", 1/4"x 1/4", 1.5"x1.5".
Ace Glass, Inc. PTFE banana stir blade, 21x87mm, 500mL flask size, 10mmshafts
21X87MM PTFE STIR BLADE
Ace Glass, Inc. PTFE banana stir blade, 35x175mm, 5L flask size, 10mm shafts
35X175MM PTFE STIR BLADE
Ace Glass, Inc. Stirbar, borosilicate glass, round, 12mm x 5mm
Stirbar, borosilicate glass, round, 12mm x 5mm
Ace Glass, Inc. Stirbars, PTFE, disposable, 50.8mmx8.0mm, pk/100
Stirbars, PTFE, disposable, 50.8mmx8.0mm, pk/100
V&P Scientific Inc STIR ELEMENT, CYLINDER, NdFeB Magnet, 42MGO, PEEK Encapsulated, Used in Bottles, Tubes/Vials, 10/pack
STIR ELEMENT, CYLINDER, NdFeB Magnet, 42MGO, PEEK Encapsulated, 11.5mm Diameter, 23.1mm Length, 150°C Max Operating Temp for Magnets
Cole-Parmer Micro Stir Bar, 5 mm L x 2 mm Dia; 1/Pk
Strong alnico V magnets with one-piece coating of PTFE.
Enterprise Technology Solutions Pacon Rotary Rack-Kraft Rolls, f/ 48" Rolls, 24"x58"x28", Gray
Easily dispense paper from 48" rolls using this sturdy rotary art roll rack. It comes with 10 dowels that will accommodate 48" x 200' ArtKraft Paper Rolls. Steel construction features a powder-coat finish for durability. Rack includes four heavy-duty, swivel rubber wheeled casters. Paper is sold separately.
Sigma Aldrich Fine Chemicals Biosciences BRAND(R) magnetic stirring bar, PTFE, cylindrical L 40 mm, bar diam. 8 mm | 10EA
BRAND(R) magnetic stirring bar, PTFE, cylindrical L 40 mm, bar diam. 8 mm | 10EA
Chemglass Life Sciences Chemglass Stirring Bar, Plain PTFE Magnetic, 20 x 6 mm (For magnetic stir plates)
PTFE plain magnetic stirring bar, 20 x 6 mm, designed for use with magnetic stir plates to provide consistent mixing. The plain shape increases turbulence at low speeds compared with smooth cylindrical bars, and the PTFE construction offers broad chemical resistance suitable for common laboratory applications.
- PTFE construction for chemical resistance.
- Plain shape increases turbulence at low stirring speeds.
- 20 x 6 mm size for small to medium vessels.
- Magnetized for use with magnetic stir plates.
- Sold individually (each).