Open Source Universal Material Science Destructive Testing Machine

Basics

• Part of the Open Source Laboratory Construction Set
• An Open Source "Universal Tester"
• Used to measure the Compressive Strength , Shear Strength , and Tensile Strength of any material made into the standard shape (usually a bar or hook
• Uses load cells, but the early versions could use Hook Style Scales
• Is almost essential if we start making any materials to provide hard, consistent evidence of material properties, especially for metals, and plastics
• Can also be used to test various weld techniques (On a purpose built small destructive test sample however for proof of concept, it doesn't replace a X-Ray Based Weld Inspection Device
• Can also test the "tackyness" / cohesion+adhesion of various glues, and greases

Existing Open Source Designs

FreeLoader

• FreeLoader
• Their Main Website

Testbot

• A ~300 USD machine
• Instructable on the device
• The Youtube Video on the Device

CNC Kitchen

• Supposeldy ~110 USD
• Uses a diy optical Extensometer
• The Youtube Video on the Device

Minimum Viable Product

• Perhaps a low strength, and "it will break anything" version
  • The former for education, and plastic workflows (as well as low level tests etc)
  • The latter as a direct substitute for high end machines

Basic Design

• Can Universal Axis develop enough torque? would a gearbox, and/or "stacking" multiple axis work?
• If not that, the Open Source Hydraulic Cylendar perhaps?
• Marcin on the Universal Axis :

"Universal axis does 50 lb precision force per 15 mm wide high precision GT2 belt strand with nema 23 motors. So in practice we can get up to 600 lb of precision drive force if we use 2-sided drive (like Y1 + Y2), 2 motors per axis, 3 belts per axis. Screws can be used for higher force.

If we want more than 600 lb force with belts, we could use belts other than the tiny GT2 belts."

• Thus it seems even a powered universal axis on both sides could do more than enough given that This filament test used a max below 200lbs (~70-80kg so a 200 lbs limit is more than enough, 1/3 of this setup)

See Also

• Materials Science Testing Methods

Useful Links

• A Page Descibing using such a Device to Check Welds