A key test is the tensile strength
of a pencil core. There are two machines that test this:
1. Hand-operated which measures in Kg and newtons.
2. A tensiometer which measures the tensile strenght of a material. We break points with this machine. This can also be used to measure the breaking point of a pencil held at an angle, the strength of a rubber at the end of a pencil, the tensile strength of the wooden barrel and bonding in the glue.
We break the pencil strips before they are put in wood and ensure they are strong enough.