Soldering galvanized steel can be challenging due to the zinc coating on the surface of the metal. If the soldering isn’t performed correctly, the life span of the joint might be shorter than desired.
There are some common mistakes that might occur when soldering galvanized steel. We’ll go through some of these occurrences and offer some tips on how to fix them.
Below are some of the more common mistakes that might occur when soldering galvanized steel:
1. Not Pre-Cleaning the Joint Area Properly
One mistake that might occur when soldering galvanized steel is not preparing the surfaces properly before soldering. Any dirt, grease, or other contaminants on the surface of the metal can prevent the solder from bonding properly. Make sure to thoroughly clean the joint before you start soldering.
Use a degreaser or rubbing alcohol to clean the joint, then use a wire brush or sandpaper to remove oxides. This will ensure that the surface of the metal is clean and ready for soldering.
2. Choose the right flux
If you are using the wrong flux when soldering galvanized steel, it can make the soldering more difficult.
For galvanized steel, it is important to use the right flux to properly bond the parts. In general, a zinc chloride based flux can get a good flow into the base metal. We also recommend a liquid flux with an active chloride formation such as the Johnson’s Galvanized Steel Flux, a blend of zinc chloride and HCL acid.
When you are working, watch the flux. If it turns black or starts to smoke, it’s time to re-apply the flux. The additional flux will help ensure that the solder will flow properly. In fact, it is always good practice to brush the flux wherever the solder needs to flow. The solder is applied after the flux; draw the hot iron down the pre-fluxed seam with the solder stick following.
3. The Soldering Iron Wasn’t Hot Enough
Another common mistake that occurs when soldering galvanized steel is not applying enough heat. If you don’t apply enough heat, the solder won’t flow properly and won’t bond to the base metal.
When the soldering is done, clean all the flux residues off to prevent corrosion.
If you have any questions about soldering galvanized steel, make sure to contact our technical sales team. They would be happy to help!