Yesterday I was introduced to the TurboShear by Malco which is one of the greatest innovations I’ve seen in sheetmetal work. Instead of using a hand or electric shear for cutting the metal this devices chucks into your cordless drill and allows much more precise cutting (such as square corners) than electric shears and is much faster than hand shears. Shears also work well for cutting vinyl, steel mesh and other similar materials. Malco also makes a heavy duty and fiber cement board version of the product though for basic sheetmetal work such as HVAC ducting the standard TS1 seems to do the trick just fine.