Everything you need to know about soldering iron tips

Soldering   |   8 min read

Soldering iron tips are the metal points on a soldering iron that you use to melt the solder, and they are an essential part of a soldering iron. Soldering iron bits come in different shapes and sizes, used for various purposes.

Some soldering tips have a rounded end, while others are pointed at one end and flat at the other. The tip size will determine what kind of work you can do with it. For example, a large tip is suitable for soldering larger pieces together (such as a printed circuit board (PCB)) but could be better for working on small wires (for instance, if you are working on wire jewellery).

Since the tips are essential to your soldering work, you’ll need to know how to purchase the right one for the job. In this article, we’ll learn more about soldering iron tips and how to choose them.

What are common types of soldering iron bits and their uses?

Tips are one of the most critical parts of a soldering iron. They’re what you use to apply heat to your work and are the only part of your iron that touches anything.

While there are various soldering bits, 5 main types exist in the market:

1. Conical
2. Chisel
3. Bevel
4. Knife
5. Needle

Conical soldering iron tips

The conical tip is the most common type of soldering iron bit because it’s excellent for general use. For example, you can use it to solder wires together or make minor repairs to electronics.

These series of tips derive their name from the cone-like shape. With its very rounded tip, you can solder from any angle, which makes this tip easier to use for general purposes.

Chisel soldering iron tips

The chisel tip with a flat surface makes it easier to solder wires with large amounts of surface area together (such as when you’re repairing an appliance). It looks like a chisel in terms of its shape. Therefore, the tip is known as a chisel tip.

Like the conical iron tips, you would use them for general-purpose soldering. Its surface area is larger than conical tips so that more heat can transfer from the tip to the electrical component. Pick this tip if you’re trying to make a quick connection, such as soldering thick wires.

Bevel soldering iron tips

These tips come in various sizes, it’s important to choose the right size for the job. If you select one too large, you might create an unexpected solder bridge. That’s when the solder flows from one point to another point on a PCB, creating an unwanted connection. On the other hand, a small soldering tip will mean you cannot reach all the points you want to.

The bevel tip is best for getting into tight spaces where other types of tips may not. You’ll recognise these tips from their curved surface. Bevel tips are for drag soldering, a technique in which you drag a line of solder across the fine-pitch pins on a PCB to solder an entire row quickly. You can apply solder on the tip and even spread small amounts on various points, whether separated or nearby.

Knife soldering iron tips

The knife soldering iron tip has a slanted end and resembles a knife. You can use it for drag solder and fixing solder bridges. It is possible to do point soldering with this tip, but it’s considerably tricky compared to the other types of tips.

Needle soldering iron tips

The fifth type of tip is the needle-type soldering iron tip. It has a pointed shape, which you can use for precise work. However, it is not suitable for soldering large components as it transfers relatively less heat than other tips.

Finally, manufacturers also create specialised tips for unique projects. You might have to purchase these tips if you have a specialised task that requires it.

What materials are soldering iron tips made of?

Soldering bits comprise these elements generally:

• Solid copper core
• Coating of plated iron
• Layered plate of nickel (behind the working surface)
• Plated chrome layer

Copper is usually the core material since it provides good heat transfer. However, the iron layer is the critical working layer, significantly affecting the soldering iron tip’s longevity.

The nickel-plated layer is a non-wetting layer. It keeps the solder from wicking away from the tip’s working surface. Without it, the solder will travel up the soldering iron bit into the heat source. That makes it challenging to apply solder to a soldering joint.

The chrome-plated layer functions as a protective layer.

How do you choose the right tip for a soldering job?

When you’re working with electronics, soldering is an essential skill. Choosing the right tip is vital if you’re looking for the best results from your soldering job.

Many different soldering iron tips are available today, making it hard to decide which one to choose. Here are some things you should consider when deciding which type of bit will work best for your needs:

• Soldering iron tip size needed
• Size and shape of components to be soldered
• Amount ofheat needed for proper soldering
• Soldering station used

Soldering iron tip size needed

First, determine what kind of solder you’ll be using, the soldering method and the type of connection you’re trying to make. Knowing these will help you choose the right bit size that’s compatible with your soldering iron.

If you choose a small soldering tip that does not transfer sufficient heat in the task you’re carrying out, weak solder joints would be created. A tip that’s too big transfers too much heat, potentially damaging both the pad and the part. In certain situations, a large bit with a high heat transfer rate can also damage the circuit board, causing problems.

Example:

If you need to reach into tight spaces while still getting enough heat transfer from your soldering iron so that everything melts together properly, damaging nothing else nearby during use, the conical tip is ideal.

Alternatively, choose chisel tips for their tapered edge which can easily get between parts, making them versatile enough for various soldering tasks. It’s also helpful in desoldering when paired with an extraction tool.

Size and shape of components to be soldered

Next, consider the size and shape of the components – will it require a large contact area? Does the PCB have narrow grooves that need to be filled? Will you be making connections between components with small points?

Example:

Conical tips can be used for both heavy-duty work make small repairs on delicate electronics. So, they are suited for small-scale electronics work on PCBs, where you will work with thin wires and surface-mount components.

These tips have a round shape that lets them focus heat quickly and evenly across their surface area, which makes them ideal for getting into tight spaces with minimal risk of damaging nearby components or tracks on the PCB itself.

Amount of heat needed for proper soldering

Before choosing a soldering bit, you should also consider how much heat your project needs.

Example:

Suppose you’re working with plastic or other materials that do not conduct heat well and require higher temperatures for proper melting, go with a bevel tip – it will allow more heat transfer through its larger surface area. Bevel tips are also recommended for drag soldering, a faster way of hand soldering PCBs.

Soldering station used

If you are buying tips for an existing solder station, make sure you purchase tips to match and operate with your equipment. For example, select Thermaltronics tip cartridges for Thermaltronics soldering systems. Using the right tips is a way to maintain and ensure your soldering equipment works optimally.

How do you take care of soldering iron bits?

Soldering iron tips are the metal points on a soldering iron that you use to melt the solder. Taking care of your soldering iron bits is essential because they can get damaged or quickly become dull if you don’t. Here’s how.

Clean your tips properly before and after use, even when they’re used by soldering robots. Keeping them clean will ensure they perform correctly and extend their life.

• Before you solder, use alcohol and a clean cloth to remove grease, corrosion and oxidation and other contaminants from the surface to be soldered.
• Always clean your soldering iron bits after every use. If any solder remains on it after use, it may not work correctly anymore. To clean your tips, you can use brass, which is softer and less abrasive. We also recommend stainless steel wool pads, which are harder but more durable. Don’t use a wet sponge, as it’ll reduce the tip’s heat and cause it to expand and repeatedly contract. This cycle induces metal fatigue, and eventually, the tip may spoil. Metal cleaning wool will not reduce the bit’s temperature while removing dirt and contaminants. Lightly dab your soldering iron tips into the wool to get rid of dirt. For more stubborn residue, grip the iron and apply pressure when rubbing it against the wool in varying strokes.
• After cleaning, wet the tip with fresh solder to stop oxidation. You can use a polishing bar if you need to carry out more thorough cleaning. Take care to use it when the tip is cold, not when it’s hot. You can use steel wool to clean off rust spots on your soldering tip. If oxidation occurs, flush it several times with a rosin-activated, flux-cored solder to remove oxidation. Once done, protect the surface with a  thick solder layer.
• Apart from cleaning, use soldering iron tips for the right job. They can be easily damaged if you should use them to pry clinched leads. This is why pliers and screwdrivers are made of hardened steel alloys, the proper tools for such tasks. Tips would spoil if you put them up to such harsh mechanical abuse.

Lastly, if your soldering iron tip becomes dull or damaged, replace it! You want to avoid ruining an entire project just because one part is not working right.