There are three types of tools that are typically used to drive screws to attach metal roofing or sidewall panels on structures. All three types of tools are comparable in price but only one is industry-preferred to use. Leland Industries provides this look at the advantages and disadvantages of each.
- Specialty Screw guns: The industry-preferred tool for installing metal panel. These are conventional 110-volt corded tools usually requiring extension cords to reach from the power source to the work site. They typically feature a torque-controlled, depth-setting feature or a simple nosepiece designed to release the screw as it seats itself to a predetermined depth (in essence, flush with the panel), with no overdrive to dimple the panel, and to eliminate screws not seating flush with the panel. They are designed to drive small diameter screws into steel or wood structures (Note: Post frame screws are usually driven with a tool operating between 1,200 and 1,800 RPM). This is the original screwdriver design for driving light-duty fasteners. Introduced in about 1964, it is still the preferred tool by many. Advantage: once the depth has been set, anyone can operate the tool and obtain perfectly seated fasteners each time. Disadvantage: extension cords are often required.
- Cordless Drill Drivers/Battery Powered Drills: the user can insert a drive socket into the chuck used to hold the drill bit and then employ the tool to drive small diameter screws. Advantage: Portability, no power cord, no need to be near a power source. Disadvantage: The operator has to release the trigger switch at just the right time to prevent over-driving and damaging the panels or, under-driving and having to go back to fully seat the fastener flush to the work surface. Skilled operators claim to be able to seat the fastener correctly every time with no depth-setting device, but with no depth-setting device, in the hands of a new employee, this can cause damage to the panels. Painted panels may be scratched and dented or screws may be left standing proud of the panel surface.
- Impact Drivers: The most recent development in tools to drive small diameter fasteners. They were originally designed for use with hex head fasteners or to facilitate driving steel nuts onto machine screws using a hit and turn motion. With each revolution the driver bit pulses or is shocked (hit) many times as the tool turns at speeds that may be higher than the 1,200-1,800 RPM recommended for driving post-frame wood screws (metal panel to wood structure). Advantages: Impact drivers are high torque, high-speed tools. This type of tool is commonly used by mechanics when loosening or installing small fasteners like lug nuts. Multiple impacts and high torque for removing small diameter parts that may have been in rusted place for years is also very useful. Disadvantages: Use of these tools, especially in inexperienced hands can cause damaged panels, broken screws, and paint or powder coating can be scratched or marred during installation.