Estimating Shearing (Sheet Metal Cutting)

The basic definition of shearing is cutting metal into smaller pieces.  If we define shearing as cutting material then not only a shear can do this process but metal scissors, lasers, punch presses, etc can also do the same function.  The shearing that is discussed hear is a machine which cuts metal with a blade.  Below is an example of an Amada shear.

Shear

Shears come in different tonnages and tolerance capabilities. The more tonnage on a shear, the thicker the material can be sheared.  A shear has both a front and back gauge which lets you measure the length of your cut from either of the two sides of the shear. Some options when estimating shear time includes setup. Setup is the time it takes set the front or back gauge to the proper measurement and verifying that it is good.  In order to get the most consistent estimates, the following questions should be answered during the setup:

• How Many Back Gauge Setups

• How Many Front Gauge Setups

By answering the above questions, a formula can be derived to give you a setup time that is answered simply versus having the information in an estimator’s head. A time of 5 minutes per back gauge setup and 3 minutes per front gauge setup. The estimator would just have to enter the quantity of cuts and how the cuts will be made to arrive at consistent setup times.

There are other setup factors to be aware of which includes “handling time” (including getting the material, stacking the material, etc.)