The Instron Tensile Tester's jaw handles had long disappeared, leaving students struggling to clamp the jaws. I approached the professor with an offer to make new handles as the Instron-branded handles were out of budget. Following this project, I became a Material Science Lab Assistant with the goal of fabricating fixtures that would otherwise be out of budget.
The handles are 304 stainless, engraved with grip-grooves and the Olin College logo for style.
This fixture was created to test welded tube samples in the Instron tensile tester, both for the Baja SAE weld test and a failure analysis project. It consists of a mild steel base plate and a welded 1" tube, along with a machined cup to apply load over the curved face.
By creating this fixture, samples can be easily tested to failure while providing valuable stress-strain data. For Baja, students use this fixture to see where the welded sample fails, passing if it fails in the base material. For my failure analysis project it provided consistent and accurate data to compare welding conditions.
To expand the testing capabilities of Olin's Instron CEAST 9340 drop tower, I designed, simulated, and fabricated a custom modular impact fixture for evaluating both flat plate specimens and irregularly shaped components. This fixture provides an adaptable platform while aligning with ASTM D7136 and Boeing BSS 726 standards.
My design approach is a two-plate system. The top plate has four low-profile hold-down clamps and dowel pins for consistent alignment of flat coupons. The bottom plate has a grid of threaded holes for fixturing irregular geometries using toe clamps.
I modeled the fixture assembly in SolidWorks and applied FEA simulations using a maximum tup energy of 243 J (22 kg mass at 4.65 m/s). I estimated impact force using a 1 ms contact duration, resulting in ~104 kN applied load for the analysis. Nearly all regions of the plates and standoffs were below the 17-4 yield strength (110 ksi), with localized yielding only at clamp interfaces. The displacement reached 0.185 inches under peak loading. This indicated sufficient strength but highlighted potential minor inaccuracies in displacement-sensitive measurements on exceptionally strong specimens.
Stress under loading conditions: 104,625N, 1ms T
Displacement under loading conditions: 104,625N, 1ms T