Aim

• To see how glue used in a 1cm overlap splice compares to the individual 1cm x 1cm glue test results.
• To see how much pressure a 1cm overlap splice can hold.

Experiment Setup

Two 1.25L bottles (90mm diameter) were used for the splice. One of the bottles was slightly heat shrunk so that it would go in the other and the edge was also curled so that glue would flow well into the join when the bottles were pushed together. The glue was PL premium. The join cured for 1 week.

Results

The splice let go at 150psi (10.3 bar).

	1cm overlap splice.
	Details of the splice.
	Splice being hydrostatically tested.
	Failed splice. The bottom edge of the left hand half can be seen where the glue separated. The rest of the splice failed in the PET plastic.

Conclusions / Analysis

There were approximately 28 square centimetres of overlap holding the two halves together. At the point of failure there were ~670kg (1480 pounds) pulling the splice apart. This is an average of 24kg / square cm when the splice failed.

The 24kg compares well to the 26.45Kg obtained in the individual 1cm x 1cm tests.