There’s more than one way to drive a screw. After all, there’s no one perfect tool to properly tighten every fastener, for every application. You wouldn’t use a 15 lb-ft pneumatic screwdriver to install the screws in a pacemaker—it’s got way too much power. It would be like watering your garden with a 2” fire hose. Similarly, you wouldn’t use a small hand screwdriver to install structural screws in an airplane. It wouldn’t be strong enough and would take far too long. Choosing the right air screwdriver is a matter of defining the needs of your application, then finding the solution that matches those needs most closely. In this article, we’ll lay out the different options available for air screwdrivers and the applications for which they’re best suited.

Comparing Screwdriver Classes

First, let’s take a small step backward and consider whether an air (or pneumatic) screwdriver is the right choice for you. Depending on what you’re manufacturing or which portion of a multi-stage assembly you’re looking at, you may be best served by a pneumatic, electric, or hand screwdriver. These different means of motive power bestow each class of screwdriver with different attributes. We’ve drawn up a simple chart below to help you compare the different screwdriver classes:

Air Electric Hand
Torque Range Highest -  The compressed air which powers pneumatic screwdrivers is capable of producing serious torque. The raw power of air screwdrivers makes them ideal for high-torque applications. Mid-range -  Electric screwdrivers can generate more torque than hand screwdrivers but are not as powerful as pneumatic screwdrivers. Their wide range makes them suitable for all but the highest and lowest torque applications. Lowest - Just ask John Henry; hand tools can’t produce the same power as pneumatic or electric tools. However, given a long enough handle and with the use of a torque multiplier, hand tools remain suitable for a large range of torque applications.
Torque Control High - Continuous drive pneumatic screwdrivers can be equipped with high-precision torque control mechanisms, which mechanically prevent over-torquing by cutting off air flow when torque is reached. Discontinuous drive, or pulse pneumatic screwdrivers, however, are not as accurate. High - Electric screwdrivers can be equipped with high-precision torque control mechanisms, which mechanically prevent over-torquing by disengaging the clutch when torque is reached.   High - Hand torque tools with cam or break-over technology mechanically prevent their operators from over-torquing with a high degree of accuracy. However, click torque wrenches only inform their operator audibly of over-torque, allowing the possibility of operator error.
Noise Level Moderate - While noise levels vary by compressor, you can plan on experiencing at least 80 decibels. Hearing protection is recommended at 85 decibels and above, which can be easily achieved if multiple compressors are working in a confined space. Low - While noise levels vary somewhat by power level, manufacturer, and load, electric screwdrivers are very quiet. As such, hearing protection is not needed. Low -  Unless you drop it on the ground or your operator is a booming conversationalist, hand screwdrivers do not make any significant noise.
Maintenance Moderate - The maintenance required for air screwdrivers depends on external factors such as ensuring the airline is clean. If routine preventative care is taken, mid-grade air tools average 200 hours between service intervals, while high-grade air tools average around 2,000 hours. Air tools can be periodically rebuilt. Regular calibration is required to ensure proper torque control. Low/Moderate - The maintenance needs and working life of electric screwdrivers vary by model. Certain brushless screwdrivers have low maintenance needs and long lifespans. However, lower-tier electric screwdrivers can require repair or replacement more frequently due to motor heat. Regular calibration is required to ensure proper torque control. Lowest - Hand tools require little maintenance to continue effective operation. Nevertheless, they must be calibrated regularly to ensure proper torque control.
Ergonomics This factor varies according to the type of air tool. Simply put, a higher torque output will lead to a greater amount of vibration and a higher torque reaction. Pneumatic screwdrivers produce higher vibrations and greater torque reactions while pneumatic pulse tools produce lower torque reactions and less vibration. The torque reaction generated by electric screwdrivers is low since these tools are mainly used for low-medium torque output. However, the torque reaction may be higher for electric screwdrivers that produce higher torque output. In these cases, a torque arm may be used to absorb the torque reaction. Hand torque tools, especially when used repeatedly or at odd angles, can cause injuries to their operators over time.
Safety Used properly by workers wearing appropriate personal protective equipment, pneumatic screwdrivers pose no undue safety concerns. If used properly by workers wearing appropriate personal protective equipment, electric screwdrivers pose few risks to their operators. However, care should be taken to prevent the possibility of electrocution by avoiding wet areas and ensuring equipment is in sound working order. Besides a skinned knuckle or two, hand tools pose little risk to their operator.
Price High - The drawback to pneumatic tools is the initial cost, which is the highest among the classes of screwdrivers. However, the upfront cost is balanced by a relatively long working life and low maintenance needs. Moderate - Electric screwdrivers, while more expensive than hand tools, do not cost as much up front as comparable pneumatic tools. Low - Hand torque screwdrivers are less expensive than electric or pneumatic screwdrivers.

Given their high power and high price, pneumatic tools are best positioned for heavy assembly and high-output operations. In addition, pneumatic tools are useful in harsher environments where electric screwdrivers may not be suitable. Electric tools have a wide range of uses and can be employed on most moderate torque and mid-to-high volume operations. Hand tools are best suited for delicate, specialty operations, such as the manufacture of miniature medical devices or other low-volume work.

Determining the Appropriate Pneumatic Screwdriver for Your Application

For the sake of this article, we’ll proceed under the assumption that after reviewing your options, you’ve decided an air screwdriver will best suit your needs. To learn more about electric or hand screwdrivers, visit these resources.

At this point, there are only a few options left to choose from. You’ll need to decide your drive style, grip style, drive size, and actuation method. To find the right pneumatic screwdriver for your operation, take a close look at your assembly. Once you’ve determined your needs, browse this list to select the right screwdriver.

Drive Style

Continuous - As the name implies, these tools apply torque continuously. When the maximum value is reached, their clutch will disengage, preventing the possibility of an over-torqued screw. While they have longer rundown times than pulse tools, continuous drive tools are more accurate, more precise, and better suited to soft joints.

Discontinuous - These tools apply torque in a series of short pulses and are commonly referred to as pulse tools. Pulse tools have fast rundown times and low torque reactions, making them a good choice for high-speed applications. While accurate, their torque application is not as precise as continuous drive tools, reducing their usefulness in areas where tight torque control is critical.

Grip Style

Inline - Intended for vertical fastening, inline screwdrivers deliver torque along the same line as the drive. Most common household screwdrivers are inline screwdrivers. In high-speed or high-torque applications, these screwdrivers can be suspended from tool balancers, reducing the strain on the joints of the operator.

Pistol - Designed for horizontal fastening, pistol grip screwdrivers deliver torque at a right angle to the drive. Pistol grip screwdrivers are capable of delivering more torque than inline or right angle screwdrivers. The maximum torque produced by a Mountz pistol grip screwdriver is 156.2lbf.in, whereas inline and right angle screwdrivers produce a maximum of 95.5lbf.in. Most common household cordless drills have pistol grips. These screwdrivers are portable and are especially useful where mobility is required.

Right Angle - Useful for tight spaces, right angle screwdrivers are gripped like inline screwdrivers, but they deliver torque at a right angle, similar to pistol screwdrivers. They are shaped similarly to common hand wrenches.

Drive Size

Fixed - If you intend to always use the same drive attachment for your screwdriver, choose a fixed size drive screwdriver. This is a sound choice for high-volume assembly and other applications where your screwdriver will be used for the same task consistently.

Adjustable - If you expect to use the same tool for applications requiring different drives, you’ll need an adjustable drive screwdriver. This may be a good choice for third-party contract manufacturers, repair workers, and assembly operations for consumer electronics, toys or other products with short life-cycles.

Actuation Method

Screwdrivers can be activated by a variety of methods, such as levers, buttons, triggers, and pressure activated heads or bits. The ideal actuation method depends on the grip style of your screwdriver. Trigger actuators, for instance, work well on pistol grip screwdrivers. Pressure activated actuators slightly reduce the strain on their operators, as they require one fewer discrete motion than other actuation methods.

When choosing any pneumatic screwdriver, one final deciding factor is the manufacturer’s reputation for quality. Investing in a line of pneumatic screwdrivers for your assembly process can be a significant outlay, so it’s important to find a manufacturer who will deliver a quality product. A strong manufacturer’s defects warranty is a necessity, but it’s best to find a manufacturer who has a reputation for delivering tools without any defects in the first place. Also, your manufacturer will be your ultimate resource for any information, service, or resupply needs you may have over the lifespan of your set of tools. Finding a manufacturer who prides themselves on customer support and service will pay serious dividends as your tools age.

However, while important, choosing a manufacturer is still one of many factors influencing your choice of air screwdriver. Finding the best screwdrivers for your business means taking a close look at your needs and comparing your options to reach the most balanced solution.

For over fifty years, Mountz has been a trusted name in the world of torque. We have a reputation for top-quality tools, expert knowledge, and sterling customer support. Our air screwdrivers are the best in the business. To learn more about our air screwdrivers, download our catalog, request a quote, or simply ask a question.