Hakko Tech Tips – How To Best Maintain Your Soldering Tips and Equipment  

August 31, 2022 WNIElectronics

In this month’s Hakko Tech Tips, we will look at some simple maintenance and inspection routines to help you achieve the maximum efficiency from your Hakko tips and equipment. By implementing routine daily or weekly procedures, you can genuinely increase the performance and quality of your soldering process, and keep equipment in tip top condition. Please see our top maintenance tips in our five point format below:

How do I keep the soldering tip in good condition?

It’s imperative to keep the soldering tip in good condition to achieve the most efficient heat transfer. For good tip maintenance, it is essential to implement important soldering procedures which will prevent the pre-tinned area from oxidation. Here are some key points to keep the tip in good condition:

If you are using a brand new tip, turn the power on and wait for the iron to heat up. When at its full operating temperature, apply solder wire to the pre-tinned area. This will protect the tip from the atmosphere preventing initial oxidation.

Always clean the tip just before soldering. Turn on the soldering iron and leave it in the iron holder until it is fully heated. Once the iron reaches the set temperature use the tip cleaner to remove the excess solder on the tip.

If the tip is cleaned after soldering, tip oxidation will occur even whilst idle in the iron holder. This is caused by exposure to the Oxygen in the working environment. It is imperative to protect the tip by applying solder, even when at rest.

Do not clean the tip when resting the iron in the holder. Leave a protective layer of molten solder on the tip.

If there is not enough solder to cover the pre-tinned area of the tip, apply some more to prevent tip oxidation.

Turn the power off when not in use.

Turn the power off if not soldering for more than 5 minutes (this is a guideline and depends on temperature).
Always keep the pre-set temperature as low as possible to produce a good quality solder joint.
Try to avoid increasing the tip temperature to more than is actually needed.

Cleaning wire or cleaning sponge?

Whilst the traditional cleaning sponge is more efficient at removing molten solder from the soldering tip, the Hakko 599B cleaning wire greatly contributes to better removal of the black oxide seen predominantly when using lead-free solders. Furthermore, because the cleaning wire will also leave a small amount of solder on the soldering tip, it also helps to provide less exposure to atmosphere and reduces the level of oxidation. There is also no cause for concern regarding any potential damage that might be caused by using the cleaning wires as they are made entirely from brass. The soldering tip is plated with iron and because this is harder than brass, cleaning with these wires does not scratch or cause any damage to soldering tips.

What cleaning solutions are available from Hakko?

Hakko’s FS-100 chemical paste can be used by setting the tip temperature at around 350℃ and dipping the tip into the FS-100 chemical paste to clean off any residue before removing the paste with a cleaning sponge or wire.

Another cleaning alternative is the Hakko FT-720 tip cleaner, which cleans a soldering tip with rotating brushes. The cleaning brushes start rotating automatically as the infrared sensor detects the presence of a tip Gently apply pressure to the required area to be cleaned, the counter-rotating brushes will remove any oxidation to provide a perfectly cleaned tip.

What maintenance procedure should I follow for my Hakko soldering station?

For station-type soldering irons, which have become mainstream products in recent years, it is recommended that customers perform regular maintenance and inspection checks, which include leak voltage, tip-to-ground resistance and tip temperature checks. The reason for this is that even if the insulation resistance is measured, it will not show the safety at the device side directly, because the inside is insulated with a transformer.

To prevent device damage and soldering failure, it is advisable to periodically perform inspections daily, or even weekly. We recommend using the new FG-101B Tester, which is our latest soldering iron tester, capable of measuring leak voltage, tip-to-ground resistance and tip temperature. Providing fast and accurate measurements, Hakko’s FG-101B provides error-free operation and comes equipped with the AS5000 long life sensor as standard, which lasts 30 times longer than a conventional sensor.

Let’s explore these 3 inspection checks further. Firstly, leak voltage should be checked periodically because if an electric current is leaked from the tip to the PWB being processed, this could have adverse effects on the components being soldered. Even though an insulative ceramic material is used, long-term use can cause the heating element to deteriorate and the leak voltage to increase. Also, an accumulation of oxides on parts such as the tip/element cover, can cause contact failure to be generated and leak voltage to increase. The lower the leak voltage, the better. All Hakko soldering iron stations have been designed with the leak voltage set to less than 2mV. If the leak voltage is higher and the heating element has deteriorated, simply replace the heating element with a new one. It is likely that the heating element will be oxidized and blackened. If this is the case, oxides are likely to have accumulated on other parts, simply remove the oxides with steel wool or fine-grade sandpaper.

The second inspection to incorporate into your routine is for tip-to-ground resistance. Oxide and flux that has stuck on the tip, element cover and nut, will cause the tip-to-ground resistance to become higher. Consequently, the leak voltage will become higher, which ultimately impacts on soldering performance. As with leak voltage, the lower the tip-to-ground resistance, the better. Therefore, all Hakko soldering iron stations have been designed with the resistance set to 2Ω or less. If your tip-to-ground resistance measurement is higher, polish the contact sections such as the tip and element cover with sandpaper or steel wool to remove any oxide films.

The third inspection involves checking the tip temperature. If the tip or element cover are oxidized, the thermal conductivity will deteriorate, causing the tip temperature to become lower than the intended set point. This may then result in soldering difficulties and can even result in component failure to due prolonged application of the soldering tip. We would always recommend measuring the tip temperature daily, or when a tip is changed, with the FG-101B tester.

Is there a correct method that I should always follow for tip replacement?

All of Hakko’s soldering systems are designed to provide ease of use for operators, therefore, tip removal is very straightforward. Flux, oxide, and carbide adhere to the enclosure pipe and the nut during soldering.
The adherence of oxide and carbide to the metal parts can negatively affect soldering quality by causing degradation of heat transfer and increase the tip to ground resistance. In the case of a soldering iron with a separate type tip and enclosure pipe, maintaining the separate tip parts rather than only the tip end helps keep the original performance. To do this, disassemble the unit to confirm the conditions of the enclosure pipe and the element support pipe. Loosen the nut with long-nose pliers to disassemble the soldering iron.

If oxidation becomes severe, seizing occurs in metal part connections, where parts stick to each other, and disassembly becomes difficult. If disassembly is impossible, replace the seized parts and clean up the disassembled parts. If there are oxides and carbide on metal parts, such as the tip enclosure, gently remove them with sandpaper. Polishing the contact area is effective in preventing seizing but avoid scrubbing too hard, and polish it with sandpaper gently.

After the maintenance, assemble the soldering iron in the reverse order of disassembly. Assemble the parts in the order of a fixing pipe/nipple->tip->enclosure pipe->nut, and tighten the nut with fingers.

Do bear in mind that it isn’t necessary to overtighten the enclosure nut upon re-fitting.

We welcome feedback from our customers and potential new customers, so please do talk to one of our team if you have any questions. Look out for next month’s Hakko Tech Tips where we will be providing more advice on how to get the best performance from your Hakko equipment.

For further information about Hakko, please visit www.hakko.co.uk.