DIY Centrifuge

Centrifuges can be built using a variety of low cost methods. These range from hand-powered “paperfuge” whirligigs to salad-spinner and Dremel-driven rotors.

See links below for several DIY centrifuges:

• Paper/String “Paperfuge”: hand-powered whirligig using a button, string, and a cardboard disc; ultra-low cost, very high RPM for capillaries.
• Wire-Swing Enhancement: adds a wire cradle so tubes hang vertical post-spin; adaptable to hand-powered, ceiling-fan, or rotary-tool drives.
• Salad-Spinner Centrifuge: manual spinner with tube holders (combs/putty/bands); ~600–950 RPM; safe, low cost, larger capacity.
• Microplate Spinner: pull-cord salad spinner with cable-tied plate inserts; quick plate clearing.
• Dremel-Driven Rotor: 3D-printed rotor on a rotary tool; up to ~35,000 RPM; requires strict guarding, balancing, and adherence to tool limits.

Test by centrifuging a dirt/water mixture.

DIY Centrifuge | Class 9 Science Lab Experiment - Cbse Academic Unit:

📄 How to Make a Lab Centrifuge - LabSupNet: https://labsup.net/blogs/blog/how-to-make-a-lab-centrifuge?srsltid=AfmBOoraGLJGQliUf_8SgAh7lYT5DaZgEkOPedEEl3VcVIJROPtzA05W

• Add a wire “swing-out” cradle so tubes return vertical after spin, reducing remixing.
• 3D print interchangeable rotors for different tube sizes (capillary, 1.5 mL, 15 mL) with generous safety factors.
• Build a clear polycarbonate shield or use a lidded salad spinner as secondary containment.
• Explore “salting out” or viscosity changes to compare separation efficiency across designs.
• Incorporate a simple optical tachometer (reflective tape + light sensor) for accurate RPM measurement.

• Always wear safety glasses; use a sturdy cover/shield around any spinning rotor.
• Balance tubes precisely; never run with an unbalanced load (excess vibration can cause ejection or breakage).
• Inspect rotors, hubs, and mounts before each run; retire any part with cracks or fatigue.
• Keep hands, hair, and loose clothing away from moving parts; never open the lid while spinning.
• Do not exceed tool or material ratings (e.g., Dremel speed limits, 3D-printed plastic strength); avoid ad-hoc power-tool hacks that lack guarding.
• Use sealed tubes for bio/chem samples and follow proper decontamination and waste procedures.

• Which design gives the highest RCF for your resources? (RCF scales with radius and the square of RPM; small-radius devices need much higher RPM to match larger rotors.)
• Why must loads be balanced? (Unbalanced forces cause large torques and vibration, risking mechanical failure and poor separation.)
• Why might a slower device still be useful pedagogically? (It demonstrates sedimentation principles safely and cheaply, even if quantitative separations take longer.)
• How do swing-out vs. fixed-angle rotors affect pellets? (Swing-out forms pellets at tube tips with clearer supernatant; fixed-angle forms sidewall pellets that may resuspend more easily.)