How to Make a DeWalt Train Horn: DIY Guide

If you enjoy DIY projects and want to create something powerful and unique, building your own DeWalt Train Horn is an exciting way to do it. You can make one using a real DeWalt impact driver or drill along with a DeWalt Train Horn DIY Kit from BossHorn. It’s not difficult, but it does take some time, a few tools, and a bit of patience.

What You’ll Need

• DeWalt impact driver or drill — even a used one, will do.
• DeWalt Train Horn DIY Kit — available at BossHorn. The kit includes trumpets, a compressor, tubing, a control board, and a remote receiver.
• Basic tools — screwdriver, pliers, wrenches, wire cutters, and drill bits.
• DeWalt 20V battery — original or aftermarket version.

The DIY Kit contains all the specialized parts, so the only things you’ll need are the drill body and your own tools.

Step 1: Prepare the Drill

Clean your DeWalt drill or impact driver and remove the front section if necessary. You’re not modifying the electronics or motor — the drill simply serves as the body for the horn assembly. Even an older, scratched drill works perfectly for this project.

Step 2: Mount the Compressor

Before attaching the air compressor, make sure it fits snugly against the drill body. You may need to slightly modify the drill housing — for example, smooth or trim small areas with a grinder, or add a thin layer of sealant or padding to ensure a tight, secure fit. Connect the compressor outlet to the trumpets using the provided tubing. Make sure the fittings are tight to prevent air leaks — this ensures full sound pressure when you blast the horn.

Step 3: Wire the Control System

Install the control board and remote receiver module. They connect easily with plug-and-play connectors, so there’s no need for soldering. The system is powered by your DeWalt battery, allowing you to trigger the horn with either the drill’s trigger or the included wireless remote control.

Step 4: Attach the Trumpets

Mount the metal trumpets using the brackets and bolts provided. Align them in the same direction for maximum sound projection. Each trumpet is made of powder-coated metal, giving your DIY horn a tough and professional appearance. Depending on your kit, you may have dual, quad, or Extreme Series trumpets.

Step 5: Test and Adjust

Insert your DeWalt battery and test the horn. You should immediately hear that deep train horn sound. If the tone isn’t strong, recheck your air seals or battery charge.

Step 6: Safety Tips

• Wear hearing protection — the sound can exceed 150 dB and cause hearing damage.
• Use outdoors only — avoid using indoors or in enclosed areas.
• The system includes an automatic battery protection feature that turns off the remote receiver after about 3 hours to avoid over-discharging the battery.

How Long It Takes

Most people can complete the build in about 2 hours. If it’s your first time doing something like this, take your time and enjoy the process. It’s a fun, hands-on project that’s as satisfying as it is loud once you finish.

Final Thoughts

Building your own DeWalt Train Horn is a rewarding experience that combines creativity, craftsmanship, and serious sound power. With the BossHorn DIY Kit, the process is straightforward and doesn’t require advanced skills. The result is a professional-quality horn that looks and sounds incredible.

If you’re not confident in your skills or simply don’t want to spend several hours building a horn from scratch, there’s an easier option. You can choose one of the ready-to-use DeWalt Train Horns available on our website. These pre-assembled models are professionally built, fully tested, and ready to blast straight out of the box — just insert your DeWalt 20V battery, and it’s instantly ready to go.