Creep Test Fixture

During the senior year of my Mechanical Engineering degree I was commissioned to design and construct a creep test fixture which could be used in the University of Idaho M.E. curriculum labs to test creep in magnetic (VCR) tape, or other light media such as fishing line.  The following is a gallery of my design.

By hanging small weights on the end of the band attached to the large wheel, a greater load is transferred to the small wheel to which the magnetic tape is attached. This constant loading (if great enough) will cause the magnetic tape to creep (stretch/permanently deform). By taking a reading from the 360 degree dial while the tape is held tight by a very small weight at the initial point, and then again after a greater weight has been added and creep has occurred, the information can be computed to find the linear creep that has occurred per unit of weight as well as at what weight creep begins to occur.

This view shows the tape (black) wrapped around the small wheel and the weight (hook) suspended from the big wheel.

This view shows the tape spanning from the small wheel to the radiused part of the apparatus where it is clamped by the brass knob on the right of the photo. Spool of VCR tape in the back ground to the left.

If you look hard you can see the tape going over the radius and under the clamping device on the right.

This photo had too much flash from the camera, but it shows the detail of the back side of the apparatus. I designed the apparatus to creep other light materials such as fishing line. In this picture you can see the winding device near the center of the big wheel at the 3:30 position. The brass handle on the right in the next photo up is inserted into this flush mounted socket to facilitate winding the fishing line or other material to secure it to the small wheel.

I was responsible for all of the design and manufacture of the apparatus. The majority of the manufacturing was done on a Bridgeport C-N-C end-mill, some however was done on a manually operated mill and metal lathe. If you have any questions please e-mail them to me.  Thank you for your interest.