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DMSBD Tech Tips
An Easy Alternative to Hot-Soldering Cable Ends
- by Ian Carsten

The construction plan for your car suggests soldering the cable ends prior to cutting to prevent them from fraying. Unfortunately many batches of cable are difficult or impossible to solder due to an anti-rust coating applied in manufacture. Another problem is the possibility of overheating the cable by getting it too hot during soldering. That anneals the cable leaving it soft and weak. This is most likely when using a gas torch as the heat source.

We’ve found that the cable ends can be fray-proofed by applying Locktite® Liquid Solder Filler. It’s sold in small tubes and can be purchased in any hardware store. The following procedure works well. First, install the cable and decide where to trim the ends. Obtain a good cutter made specifically for cutting hard wire rope (braided steel cable). These tools have hardened steel cutting edges that are shaped to keep the cable nearly circular while cutting. That makes a clean cut without fraying the individual strands of wire. Many bicycle enthusiasts have such cutters for trimming brake and shifter cables.

Don’t use straight-jawed cutters because they will flatten the cable and splay the ends. The best tool for the job is the Swiss made Felco C7. This tool can be ordered from Bicycle Tools Etc. at www.biketoolsetc.com. Or you may obtain a similar tool from your local cycle shop.

Before cutting the cable, clean the area carefully with carburetor cleaner to get any trace of dirt or oils off. Cut the cable and apply the liquid solder filler. The easiest way to do this is to place the cable end into the mouth of the tube and push the tube over the cable until a coating of the solder filler is left on the cable. Let it dry and harden at least an hour. If the coating isn’t thick enough, simply repeat with another coat until you are satisfied.

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