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 Veco Parallel Bar w/ Divider Handle R200D, 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: 125 µm
Hole: 85 µm
Bar: 40 µm
Analytical Sales & Services Well Tray Loaded with 8x30 Shell Vials, with 99685 Silicone Cap Mat, and 13258 Stir Bars
Well Tray Loaded with 8x30 Shell Vials, with 99685 Silicone Cap Mat, and 13258 Stir Bars
Analytical Sales & Services Barcoded 8x30 Shell Vials in 96 Position Format, with 99685 Silicone Cap Mat, and 13258 Stir Bars, in Clam Shell (no well tray)
Barcoded 8x30 Shell Vials in 96 Position Format, with 99685 Silicone Cap Mat, and 13258 Stir Bars, in Clam Shell (no well tray)
Electron Microscopy Sciences Spinbar Circulus™ Dumbbell Stiriing Bar 52mm White
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: White
Electron Microscopy Sciences Glass Rods, 200 mm Long
Useful tool for all laboratories needs to stir / mix substances. Glass rods are 5 mm diameter.
Electron Microscopy Sciences Spinbar Circulus™ Dumbbell Stiriing Bar 32mm 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
Hach Company Stir Bar, Magnetic Egg-Shaped
Designed specifically for round bottom flasks and vessels. The PTFE coated, egg-shaped, magnetic stir bar fits the round bottom for uniform stirring without restriction. Recommended for the following round bottom flask sizes: 10, 25, 50, and 100 mL.