Creating a strong, accurate, and durable linkage is one of the most important steps when building or repairing an RC airplane. Your control surfaces rely on precision hardware to ensure smooth, predictable movement—and poorly made linkages can lead to sloppy control response or even in-flight failure. DU-BRO threaded rods and threaded couplers are designed specifically for this purpose, offering a secure and professional-grade solution for customizing linkage lengths.
In this DU-BRO 101 guide, we’ll walk through the complete process of building your own custom linkage using threaded rods, threaded couplers, and clevis links—along with best practices for soldering a strong, void-free joint. DU-BRO hardware is known for reliability, and using these parts correctly will give you a linkage you can trust.
DU-BRO offers a wide selection of threaded rods, couplers, and linkage components for airplanes, helicopters, cars, and boats.
Why Use Threaded Rods and Couplers?
Threaded couplers include a 1 cm deep internal cup that accepts a threaded rod. Once soldered, this creates a strong metal-on-metal joint capable of handling vibration, high loads, and flight stress. By cutting your rod to exact length and soldering it inside the coupler, you get a perfectly custom fit every time. This strength is especially important on larger models or on high-stress surfaces like elevators and rudders.
When paired with DU-BRO Kwik-Links or Safety Lock Kwik-Links, you get a linkage that remains secure even under heavy aerodynamic loads.
Step-by-Step: How to Build Your Custom Linkage
1. Measure the Required Rod Length
Use a metric ruler to measure the distance between both linkage points. Remember that the threaded coupler has a 1 cm deep cup, so accommodate that when marking your cut line.
2. Cut and Prepare the Rod
Cut the rod using side cutters or dykes. Then rough up the cut end with old sandpaper. This increases surface area so solder can flow and grip better. Clean the roughed-up end using rubbing alcohol or other degreasers.
3. Add Flux and Assemble the Joint
Dip the cleaned threaded end into soldering flux, then insert it into the coupler cup. Using mechanical silver solder—NOT electronic solder—form a half-circle bead on the joint. Place the parts in helping hands so the rod points downward into the coupler.
4. Heat the Joint Properly
Use a small butane torch or similar heat source, applying heat only until the solder stops boiling. This ensures trapped air escapes so there are no internal voids. Allow the solder joint to cool.
5. Clean the Solder Joint
Once cooled, clean the joint. A drop of ketchup works surprisingly well—the mild acid helps brighten and clean the metal.
DU-BRO offers helpful tools for soldering and linkage preparation, including pliers, cutters, and clamps.
Install Clevises and Attach to Your Control Surface
Thread DU-BRO clevis links onto the finished couplers and install them onto your control horn and servo arm.
The result is a custom linkage that is strong, precise, and built to last—ideal for any sport, scale, or aerobatic model.
Using DU-BRO threaded rods and couplers ensures that every control input from your transmitter translates cleanly and accurately to your aircraft’s control surfaces. With proper measurements, careful soldering, and DU-BRO’s proven hardware, you’ll have a linkage system you can trust in the air.
* Silver solder used in video*
