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During the set-up for the first test, we found that a certain clocking of the MP tube and the coupler led to the piston being misaligned with the cup and diaphragm. This likely is caused by the holes being machined slightly off from a level horizontal.
Jan 26, 2019 Piston Test 1.mp4
In the second test, the Forward Retention Ring struck the MP tube after detonation of the firebolts. After the test, we say saw that there was bolt shear-out on the cup. This could have been caused by the FRR hitting the MP tube. We also noted that the piston bolts were loose during de-integration. Perhaps they They may had not been fully tightened with a hex wrench, which could have also contributed to bolt shear-out.
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