Concrete Drills: Increase Uptime, Extend the Life and Reduce Costs

Downtime is a four-letter word in the road repair business, and whether you’re looking at hours or days rests largely on your concrete drill. To make sure it’s up to performing day after day to the best of its capabilities, a little upfront investigation and preventative maintenance are a must. By implementing a few best practices, you’ll spend less on repairs and new parts and keep that dreaded D-word to a minimum.

It’s All in the Homework

Long before you hit the pavement, do your research on the different types of concrete drills and their components and how each can impact maintenance and performance. For example, drills operate with either a roller bearing feed system or a nylon pad system. With a roller bearing feed system, rollers gently move the gangs forward and backward on the carriage without causing friction. With a nylon pad system, however, the pad slides across the carriage to move the gangs forward and backward. This creates friction that causes the pads to loosen and wear much faster, which results in more maintenance, replacement parts and downtime. In addition to quality components, it’s important to work with a manufacturer that maintains an extensive inventory of parts and can provide them in a timely manner. Getting a replacement part in a day vs. a week can have a major impact on productivity.

Keep an Eye Out

While you might have selected a concrete drill with high-quality components, you’re not done yet. You also need to perform regular maintenance checks to ensure it’s operating at full capacity. Oil is vital to the performance of your drill, and if you’re not using the right kind you could be putting your engine and components in jeopardy. Rock drill oil is the only kind of oil you should be using in the reservoir. Other lubricants, like pneumatic tool oil and automatic transmission fluid, are too light for concrete drills and will burn off quickly, which could damage the drill motor. In addition, they contain synthetics that can damage hoses and O-rings.

Once you have oil in your drill, don’t forget to check it often — as frequently as once or twice a day depending on the model and if your drill is in high use. If the oil reservoir empties, the motor will slow and the power will decrease until the lack of lubrication causes it to seize. Also remember to keep the fittings and guide wheels well greased.

In addition to keeping the oil in check, you’ll also want to keep an eye on the nuts and bolts around the drill system, since the vibration of the unit can cause them to loosen over time. Look at the trunnion bolts often, which secure the latch that holds the bit in the drill. Also check thru bolts, which are the long bolts that hold the drill motor together. If either the trunnion or thru bolts become loose and break, it’s not only inconvenient but costly as well. These bolts also can break as a result of dry firing, which occurs when the drill is operating, but not drilling into anything. To prevent this, only run the drill when the bit is touching the concrete and drilling into the slab. Also, be sure to turn the motor off before retracting the bit from the hole.

And, finally, be sure to keep your concrete drill clean. Dust can accumulate quickly on parts and if allowed to become wet, can quickly turn into concrete, which has a significant effect on performance. Use an air hose or pressure washer to thoroughly clean your drill daily.

Sizing It Up

The most important thing to keep in mind is air. Your drill won’t operate without it and will perform poorly without enough of it. First, make sure you have the right size air compressor. For example, many models require 100 cfm per drill motor, so if you have a two-gang unit, you will need 200 cfm, if you have a three-gang you will need 300 cfm and so forth. If you are using an air compressor that provides less air than what is required, it can starve the drills of air and greatly reduce the power and speed of the drill. Using a slightly smaller air compressor than recommended might work when drilling small diameter holes — 1 in. or less — but for larger holes the drill will slow down considerably or not work at all.

The same can happen if your air hose is not the proper diameter. If it’s larger than what is recommended, it will have no effect on the drill’s performance, however, a hose with too small of a diameter can’t transport enough air to the drill. As a result, power and drilling speed are greatly reduced. If you are using a multi-gang drill and want to check if you have the right size air compressor or hose, turn off all but one of the drill motors. If the remaining drill motor speeds up, then there’s not enough air volume to keep the drills operating at full capacity. Always refer to your owner’s manual for recommended hose sizes and cfm requirements.

Taking a Break

If your drill is going to be inactive for a while — whether it’s through the winter or just a few days — it’s a good idea to lubricate the interior parts of the rock drill to prevent rust from forming. Rust can develop from the tiniest amount of moisture, and it only takes a simple speck to cause the drill’s motor to seize. To lubricate your drill motor, disconnect the hose from the motor and pour a small amount of any type of lubricant (rock drill oil, pneumatic tool oil, even diesel fuel) directly into the motor. Run it at half throttle for a moment to thoroughly coat the interior parts of the drill motor. Drain any condensation from the machine’s filters and cover the drill with a tarp if it will be stored outside.

When you’re ready to start using the drill, ensure the oil reservoir is full and bolts are tight. If it has wheels, check the tire pressure and blow out the hose that runs between the drill and compressor to ensure it’s clean. If dirt or debris accumulated in the hose, it could be forced into the motor when you start it and affect your drill’s performance.

The Last Word

There’s nothing that stops a project in its tracks like downtime. While it’s impossible to censor the D-word altogether, with a high-quality drill, regular maintenance and the right preparation, you can reduce it substantially. Because less downtime means more time to finish your project, but most importantly, it means lower costs and higher profits.

Randy Stevens is vice president of sales with E-Z Drill Inc., based in Stillwater, Okla.