The Weller®PES51 tools are interchangeable without the need to make any adjustments to the station "Offset" function. This is made possible by the use of a precision temperature sensor; which is positioned deep inside the tip to insure rapid response to soldering load variations.

**Caution:** Do not use hot-air on surfaces you don't want ruined. Having a piece of scrap wood or something similar to work with hot-air on is highly recommended. Third hands or other vice grips help tremendously. Remember, metal heat sinks and PCBs with ground planes can make reworking take a lot longer.

**Note:** Set the temp and air-flow to the appropriate settings (slightly higher than the melting point of the solder, and not too much air to blow your parts away). We recommend setting the air flow and temperature knobs to the middle and then test reflow on a small component.

- **Polarized Components** - Parts that have been placed incorrectly (backwards, shifted x degrees off). These include ICs, diodes, some capacitors, connectors, etc. - **Tombstone Parts** - This is when a part (usually a resistor or capacitor) reflows only on one side. The part usually sticks strait up resembling a tombstone. - **Cold Joints** - This is similar to a tombstone except the parts might not be sticking strait up, making it harder to see the connection that is not being made. - **Removing Defective Parts** - Sometimes, during the IC manufacturing process, errors can arise and go unnoticed. These ICs are then placed on perfectly good PCBs. Hot-air is great for replacing these bad parts. - **Missing Components** - The smaller the component, the easier it is for it to disappear. This can happen before or during reflow, resulting in a spot where something should be, but isn't. Hot-airing a new part in its place is a snap with this rework station. - **Unintentional Solder Jumpers** - If too much solder or solder paste is used, the result can be jumpers on one or more of your surface mount IC's legs. Hot-air can sometimes be used in conjunction with a [flux pen](https://www.sparkfun.com/products/14579) to remove these pesky buggers.

- Salvaging electronic components from old PCBs. - Reflowing [solder paste applied with a stencil](https://cdn.sparkfun.com/datasheets/Kits/SFE03-0010-SimonSMDStenciling-Kitcard-ReaderSpreads.pdf) between SMD components and a PCB. - Shrinking [heat-shrink](https://www.sparkfun.com/products/9353) to secure wire connections. - Heating up and bending certain plastics (with the correct settings). - Heating up hot glue to remove or reposition items that were glued incorrectly.