Printed circuit boards are parts that make an electronic device function as it should. Sometimes, these devices don’t function as expected. Errors occur when working with or fabricating a printed circuit board. Therefore, fixing these errors requires specific tools.
The Rework station is one of the most important tool for performing reworks and repairs on a PCB. This article offers detailed information on what a rework station is and how to use it.
What is a Rework Station?
A rework station is a tool that enables easy desoldering and adjustment. Also, rework stations are de-soldering stations. The soldering function of these stations enables operators to use metal solder to repair metal. Rework refers to the repair of an electronic circuit board. It usually involves re-soldering and desoldering of surface mount devices. Therefore, rework stations are tools used to perform re-soldering and desoldering.
Printed circuit boards and other electronic components feature various working parts. Most of these parts are usually made of metal. After removing the component, the technician must maneuver and remove some metal parts to work on. Extreme heat can melt metal to a point where it can bend and move. Also, rework stations are specially designed to do this.
Rework stations can produce hot air temperature to bend and move metal parts. Also, the hot air produced from the rework stations can melt solder. A rework station usually features a hot air gun. Also, this tool is ideal for less sophisticated work like melting solder in a bigger area. Rework stations can heat large areas effectively. Therefore, they are ideal for surface mounting reworks where there are delicate components involved.
What is the Function of Hot Air Rework Stations?
Hot air rework stations utilize heated air to evenly heat the area of the circuit board you are working on. You may need to get rid of old solder while repairing and resoldering a fixed area on a circuit board. Also, hot air rework stations send hot air to heat solder for resoldering or removal. These rework stations are available in various sizes to enable rework on different PCB sizes.
Hot air rework station features a hot air gun that melts the solder and allows you to remove multiple components. This process saves a lot of time. Also, hot air rework stations feature a pump that circulates fresh air over a hot coil. Hot air rework stations are widely used in the PCB industry. They have a solder feature which helps to add extra components to a PCB.
The desoldering tool in the rework station can remove polarized parts. You can resolder the part after reversing it. Most hot air rework stations feature vacuums that suck the old solder. Also, hot air rework stations can help to secure loose connections or repair damaged components. Hot air rework stations are suitable for reworking or removing surface-mounted components.
Hot air rework stations can function as soldering stations. Also, you can remove old or broken components with a hot air station. When using hot air rework stations, you need to select the correct nozzle size. Then, set in the airflow and temperature rate to melt the solder on the board. Also, the solder type will determine the airflow and temperature rate. Also, hot air rework stations feature memory temperature function and tight temperature tolerances.
Hardware Features of Rework Stations
All rework stations are similar in how they operate. However, the energy output, style, and placement of various components may differ. Below are common hardware features of rework stations:
Temperature control
This hardware feature is crucial in any rework station. Also, it enables operators to adjust the temperature at any time. You can simply turn the temperature setting knob to adjust the working temperature range.
Wand holder
The wand holder is on the side of the work station’s casing. Also, it is a good place to keep the wand when not in use.
Air flow grade
The airflow grade is a dial located on the hardware. Also, it enables the operator to adjust the hot air flow rate from the hand tool.
Hot air gun
This handheld tool helps the operator to apply heat to metal solder. Also, the metal solder will need to melt well to perform repairs and reworks.
Nozzle
Nozzles are available in different sizes. The bigger nozzle is ideal if you are focusing hot air around a large area of the board. Smaller nozzles are great for focusing hot air on smaller components.
The power switch is very easy to locate. To turn on the hot air rework stations, you just need to switch to “ON.” Also, turn off the rework station by moving the switch to “OFF.” When you switch off the rework station, it will not go off immediately. The device will keep blowing air until the air temperature goes below 100 degrees Celsius.
What Components can Rework Stations Remove?
Hot air rework stations are an important tool for reworking a printed circuit board. Rework is a term commonly used in the PCB industry. It simply means you are repairing an already reflowed circuit board. Also, rework stations can remove or replace components and parts like:
Missing components
Smaller components can easily disappear during PCB assembly. Also, this can occur during or before reflow. Hot air rework stations can help to heat a new part in its place.
Polarized components
Polarized components are incorrectly placed parts. These include connectors, ICs, and capacitors.
Defective components removal
Errors can arise during the IC production process. Also, these errors might be unnoticed. PCB manufacturers can place these defective ICs on functional PCBs. Therefore, hot air can help to replace these bad parts.
Tombstone parts
Tombstone parts occur when a part only reflows on one side. Also, these parts stick straight up and look like a tombstone.
Solder jumpers
Solder jumpers are a result of too much solder paste or solder on the surface mount IC’s legs. Also, hot air can work with a flux pen to remove these buggers.
Cold joints
Cold joints are similar to tombstone. For cold joints, the parts don’t stick straight up. Therefore, this makes it difficult to notice them.
How to Use a Hot Air Rework Stations
Hot air rework stations can be easy to use when operators follow proper guidelines. Also, these devices are not suitable for surfaces you don’t want to ruin. Here are tips on how to use hot air rework stations.
Select your nozzle
Select the proper nozzle size for your rework. After this fix the nozzles the wand and use a screwdriver to hold the screw in place. Plug the standard plug into your US outlet. Also,the blower and heating element will stay off until you switch on the power.
Power on
Immediately you switch on the power, the heating element will produce very hot air. The red LED will pulse. This indicates that the device is ready to melt. Also, make sure you wait for the hot-air station to heat up before utilizing it.
Adjust temperature and air
The hot air rework station features two control knobs. One knob is for temperature while the other knob is for airflow. Ensure you set the air-flow and temperature using the right settings. Also, the airflow and temperature should be a bit higher than the solder’s melting point. It is advisable to set the temperature and air flow knobs to the middle.
Rework
Rework begins when you have got the appropriate settings for your airflow and temperature. Focus the nozzle at the exact area you intend working on. Move the nozzle until the solder starts flowing. Also, the solder should be molten. After this, carefully reposition or remove the part you need to rework. You will need a pair of tweezers for this.
Cool down
Ensure you switch off the power once you have done rework. This will allow the station to cool off. Also, this station has an automatic cooling function.
Safety Tips When Using a Heat Gun
It is crucial to know how to use heat gun correctly to avoid damaging the circuit board. When working with heat gun, you need to direct the heat to the area that needs rework. Also, heat guns are available in several designs. Some heat guns sit on a bench without any form of support. In such a case, set the heat gun to the correct area. Below are safety tips when using a heat gun station:
- Ensure you wear eye protection.
- Avoid operating a heat gun near combustible materials.
- Also, protect your workbench from heat damage by using a silicone mat.
- Use heat guns with an extension cord only when necessary. This is because heat guns draw much power.
- Don’t place the heat gun nozzle close to any other object when it is still hot.
- Ensure you turn off the heat gun before resting it on a surface.
- Don’t operate a heat gun while the nozzle is well pressed into the workpiece surface. Also, placing the heat gun in that way will restrict airflow.
- Never insert foreign objects into the heat gun’s nozzle.
- Also, ensure the heat gun cools down before you put it away.
Common Problems that Occur when using Hot Air Rework Stations
H-E error
The H-E error occurs when there is a heating error. Also, this error might be a result of improper connection of the heating element. Therefore, it is advisable to always check the connections to determine if there is need to re-seat the heating element.
Too high air
You might start noticing some small projectiles getting away from your circuit board if the air flow is too high. Those projectiles are your part. Therefore, it is advisable you start at a lower rate of air flow and move up according to your needs.
S-E error
This error refers to Sensor Error. S-Error indicates that failure in the heat sensor. Also, S-E error is a common error that can leave after messing with the dial. You can revive the rework station by removing and re-fixing the heater.
Pulled pads
A pulled pad is another common problem that could occur when you push the pad too hard. Therefore, it is advisable to nudge the part gently when checking to see if it is ready to move.
Low airflow
You could experience low air flow when you turn up the “Air” Dial. Therefore, ensure the nozzle is well attached. If you do this, you will get more air flow via the handle of the hot air rework station.
What is the Difference Between Rework Station and Soldering Station?
Soldering is an integral part of PCB manufacturing. A soldering station and rework station are the two important tools for soldering. Also, these two stations both deal with soldering; however, they have different scopes of use.
- A soldering station is more ideal for precision work like through-hole soldering. A hot air rework station can work with any component. It is much better for less sophisticated work like melting a solder in a bigger area. However, rework stations don’t have the same precision as soldering stations.
- The basic part of rework station is a heat gun. On the other hand, a soldering station features a few different basic parts. Also, a soldering station features a sponge, a soldering iron stand, and a soldering iron.
- The size and weight of rework stations are more than that of soldering stations. Therefore, this makes it more difficult to move rework stations. Due to the smaller size of a soldering station, it is easier to control and move.
- Soldering stations are ideal for attaching two parts or components at a small point. A hot air rework station can’t do the same. Also, a hot air rework station doesn’t focus all its heat on a particular spot. Therefore, it can prevent certain drawbacks related with a soldering station.
- Hot air rework stations don’t have direct contact with whatever they are heating. Their tight temperature tolerances make them heat the appropriate spot. Soldering stations have direct contact with the parts they are soldering.
- Also, hot air rework stations are more expensive than soldering stations.
Conclusion
Hot air rework stations are crucial in PCB manufacturing. They are quick at removing large amount of solder. Therefore, this makes hot air rework stations a suitable choice among PCB manufacturers. Also, rework stations can deal with larger components and those prone to damage. The tight temperature tolerances of a hot air rework station contribute to its functioning.
