DIYbio Centrifuge V 3.0

UPDATES We've enlarged the length/width from 100x100mm to 104x104mm. We had our Eppendorf tubes making contact with the sides under certain circumstances. If you downloaded the files before June 24, 2019 you have the smaller version.

We've added a motorMount_V2 STL file. This has hex spaces for the M3 nuts to fit into. This helps prevent them from coming loose from vibrations and makes tightening the bolts possible without opening the case. If the nuts don't fit in at first, put them as far in as possible, and drive the bolt in as you would if it did fit and it will tighten them all the way down.

Introduction

This V3 of our DIYbio micocentrifuge. A video overview can be found here: https://youtu.be/Od_wNhkoEak

Last photo shows a V3 prototype (left) with V2 (right).

New Features

1. Rotor is lighter and press-fit (there is a lowpoly, and a hi-res OPENSCAD version;
2. Rotor is below the platform;
3. Microswitch plunger located slightly below the platform to prevent accidental activation when lid is open;
4. Stronger hinges;
5. Separate motor mount to allow for various motor sizes;
6. Smaller profile, less top-heavy;
7. Offset bolt-latch making it easier to insert/retract retaining bolt and;
8. Containment compartment to better isolate electronics from rotor.

Additional Features

Incorporates 12V DC motor;
microswitch for auto-cutoff when cover is open;
rocker switch and;
extra space for Arduino Nano;

Description

It uses a 12V DC motor and a simple rocker switch. It also has provisions for adding in a microswitch (16x28mm, no arm) and enough room for adding in a micocontroller (like an Arduino Nano) to add timing and cycle functions.

The original SketchUp 2019 file (.skp) is included, so is the OpenSCAD file for the higher-resolution rotor.

Instructions

Requires friction welding (or glue) to seal the acrylic between the top/bottom of the lid.

The rotor is press fit onto the motor shaft. If it is loose, apply a tiny bit of hot glue.

The hinges use M3x 30mm bolts and nuts. Any M3 bolt can be used to hold the platform onto the case (at the bottom).

Improvements Still Coming

1. Solid lid cover for those who don't have access to acrylic;
2. Video demonstration/tutorial;
3. Different rotor/motor solutions to improve balance.