Help with Tensile Testing and Tensile Grips

1. MA089/MA564: https://www.biomomentum.com/accessories/sample-holder-c-shaped-tensile-grip-opening-10-mm/
   
2. MA563: https://www.biomomentum.com/accessories/sample-holder-c-shaped-tensile-grip-opening-8-mm/
   
3. MA626: https://www.biomomentum.com/accessories/chamber-d-98-mm-2-walls-50-8-and-76-2-mm-for-sample-holders/

• Video playlist: https://www.youtube.com/playlist?list=PLNlS2DfX2uD-z9EYQtLZI8v8e1rarf4Z0
• PDF version: LABORATORY MODULE TENSION AND RUPTURE OF SKIN

 Here are some things to consider:

1. Always be careful when handling the load cell. In particular, avoid tightening a grip that is attached directly to the load cell. This applies off-axis forces which could damage the sensor.
2. A “Find Contact” function in the “Negative” (up) direction can be used to apply a certain preload to the sample as in the above tutorial.
3. Otherwise, common tests are Move Relative (negative direction), Stress Relaxation and Sinusoid (dynamic test).
4. To install the sample, here are some steps:
1. Tighten the sample in one of the grips.
2. Attach this grip to the load cell (top grip).
3. Install the lower grip without the sample.
4. The two thumbscrews on each grip are used to lock them in place.
5. Using the manual controls in the software, slowly lower the top grip until the sample is within the lower grips.
6. Tighten the lower grips.
7. Apply a preload.
8. Measure the distance between the grips as your “gauge length”.

To obtain more length, you can either remove the accessories on the lower part of the system (manual vernier stages, etc.) or you can raise the vertical axis (it is only held by 4 bolts). Here is a reference image and a video reference: https://www.youtube.com/watch?v=SDZYO9za2pQ.