Weller blog

Water-soluble fluxes typically used with lead free solder can quickly wear a soldering tip to the point of unwettability. This is especially true when using thin solder wire with little flux content. The intensive cleaning that is necessary with lead free solder reduces the amount of tin, exposing the tip to oxidation. Black oxide layers that form on the surface of the tip must be removed, or the tip will soon become permanently unwettable.

In addition to the use of a traditional wet sponge for cleaning, Weller now offers a solution for gentle tip cleaning - the Weller Dry Cleaner WDC (order no. 0051512499). The WDC uses a special metal wool ball. Dry cleaning is performed in a two step process. First, excess solder is removed from the hot tip by tapping the soldering pencil lightly on the soft rubber edge of the solder collection box. Second, pushing the tip into the metal wool ball and turning cleans the tip. After cleaning, there is still a fine layer of tin on the tip, which will help avoid fast oxidation of the iron layer.

In addition, use of the WDC will not shock the tip, because the temperature remains constant during the cleaning process.

The sturdy plastic and rubber housing of the WDC is ESD safe.

The oxidation of the soldering tip is a growing issue due to the increased use of lead free solders.  The fluxes typically used with lead free will agressively attack the iron plating of a tip, resulting in decreased tip life.  Follw these steps to help extend the life of your tips:

• Use a  Weller WPB1 polishing bar to remove surface oxides. You may need to follow this procedure frequently if you are using fine point tips.  While the tip is cold (never use the WPB1 while the tip is heated), lightly rub the polishing bar on the tip until clean. If the surface oxide is heavy, more pressure may be needed.
• The tip should be immediately re-tinned as soon as it reaches the melting point of the alloy being used in the application.
• Tip Tinner's may also be used to restore the tip, especially when surface contamination (darkened appearance) is present.

Key Points to Remember:

1. Always keep the tip coated with a thin layer of solder.
2. Use fluxes that are as mild as possible but are still capable of properly cleaning the tip and the metals being soldered.
3. Keep the soldering iron temperature as low as possible while maintaining enough temperature to quickly solder a joint (5 seconds maximum for Eutectic or low melting point alloys / 8 seconds maximum for Lead Free alloys)
4. Use as large of a tip as possible to perform the application for maximum heat transfer.
5. Use a tip with the shortest reach possible for the best thermal performance.