You are required to provide two ASTM D 3039 tensile specimens taken from what remains of your wet lay-up panel. A copy of the ASTM Standard can be seen in the "ReadOnly" folder on the "ClassStorage" drive (width = 1", overall length = min. of 9", and grip length = min. of 2" each end).

One specimen is to be taken directly from the panel as initially fabricated. The second specimen is required to be cut in half and, in order to transfer the tensile load across the specimen, you need to design a bonded joint with the remaining pieces from the panel. The ends of the bonded joint specimen must line up with each other (i.e. so when tested no moment is produced). The control specimen and the cut specimen need to be approved (specimens/remaining pieces marked) before any bonding takes place.

All teams will use the same adhesive, LOCTITE-EA-E-20HP epoxy adhesive. See the product data sheet (available on the internet) and review the SDS in the department's database. The adhesive system and dispensing equipment can be found in the Manufacturing Lab. The two component epoxy adhesive is properly metered as it is dispensed. There are mixheads available, but it is just as easy to dispense into a small cup and thoroughly mix with a stir stick.

Both the bonded joint and the uncut specimen will be tested to failure and the two strengths compared. Your grade will be based on the specimen dimensions (width in the gage section, overall length, and miminum grip length, 20%), the visual appearance of the bonded joint (alignment, adhesive cleaned up, etc. 20%) and how effectively the joint transfers the load (60%).