How to Use a Converter in Your Fountain Pen: Step-by-Step Guide

Quick Answer

A converter is a refillable ink reservoir that fits inside your fountain pen, letting you use bottled ink instead of cartridges. To use one, insert the converter into the pen, dip the nib in ink, and twist or pull the piston to draw ink up. It’s a simple, eco-friendly way to enjoy a wider range of inks.

If you’ve just bought your first fountain pen, you might be wondering how to use a converter. Many pens come with a cartridge, but a converter lets you use bottled ink, giving you access to hundreds of colors and finishes. In this guide, we’ll walk you through the steps of filling your pen with a converter, and we’ll point out common mistakes to avoid.

We’ll also compare converters to cartridges so you can decide which is right for you. And because a good pen deserves good protection, we’ll mention a few leather pen cases that keep your writing tools safe.

What Is a Fountain Pen Converter and Why Use One?

A converter is a small, refillable device that fits inside your fountain pen in place of a disposable cartridge. It typically has a piston or squeeze mechanism that draws ink from a bottle into a reservoir. Using a converter lets you choose from a vast array of bottled inks, including shading and sheen varieties that aren’t available in cartridges.

Converters are also more economical and environmentally friendly in the long run, since you’re not throwing away plastic cartridges. Many fountain pen enthusiasts prefer converters for the flexibility they offer—you can switch colors whenever you like, and you’re not tied to a brand’s cartridge system.

When you’re ready to carry your pen, a leather pen case protects it from scratches and leaks. For example, the Leather Zippered 3 Slots Pen Case from Galen Leather is a popular choice for EDC, as it holds up to 145mm pens and includes a credit card slot.

• Converters work with any bottled ink, so you can explore brands like Diamine and Teranishi.
• They’re more eco-friendly than cartridges because you’re not discarding plastic after each use.

How to Fill Your Fountain Pen with a Converter

Filling your pen with a converter is a straightforward process, but a few details make the difference between a clean fill and a mess. First, ensure your pen is clean and dry. If you’ve used it with a different ink before, flush it with water and let it dry completely.

Now, insert the converter into the pen’s section (the part that holds the nib) if it isn’t already installed. Then, dip the nib fully into the ink bottle, making sure the opening of the feed is submerged. Turn the converter’s piston or squeeze the reservoir to expel air, then release to draw ink in. Repeat this a couple of times to get a full fill.

A common mistake is to fill too quickly, which can trap air bubbles and result in a partial fill. Another mistake is to forget to expel the air before filling—this leaves a large air pocket and reduces ink capacity. Wipe the section with a tissue or cloth before reattaching it to the barrel to avoid inky fingers.

After filling, store your pen nib-up or horizontally to prevent leaks. If you’re traveling, consider a leather pen case or a zip folio to keep your pen safe.

• Always expel air from the converter before dipping the nib in ink.
• Fill slowly to avoid air bubbles and ensure a full reservoir.
• Wipe the section after filling to prevent ink on your hands.

Common Mistakes and How to Avoid Them

One of the most common mistakes when using a converter is over-tightening the converter when inserting it into the pen. This can crack the converter or push it out of alignment, causing leaks. Screw or push it in until it fits snugly, but don’t force it.

Another mistake is using the wrong converter for your pen model. Converters come in standard international, proprietary, and other types. Check your pen’s manual or consult the manufacturer to ensure compatibility. If you’re unsure, look for a converter that matches your pen’s brand.

Some pens have a transparent barrel, making it easy to see how much ink remains. Others are opaque, so you might not realize you’re running low until the pen writes dry. Check your ink level periodically, especially before long writing sessions.

Finally, don’t leave your pen inked and unused for weeks—ink can dry and clog the feed. If you’re not using the pen for a while, empty the converter, flush the pen, and store it dry.

• Use the correct converter type for your pen brand.
• Don’t force the converter; if it doesn’t fit, it’s likely the wrong type.
• Clean your pen regularly to prevent clogging.

Converter vs Cartridge: Which Is Right for You?

The main difference between a converter and a cartridge is convenience versus flexibility. Cartridges are pre-filled and easy to insert, making them perfect for travel or for those who don’t want to carry a bottle. Converters, on the other hand, allow you to use any bottled ink and are more economical over time.

If you’re just starting, you might prefer cartridges for simplicity. But if you enjoy exploring different ink colors—like Diamine Flower Burgundy Rose or Teranishi Guitar Taisho Roman Haikara Ink—a converter opens up a world of options.

A good compromise is to carry a converter for everyday use and keep a few cartridges as backup for travel. Many pens can accept both, so you have the flexibility to switch.

When you do switch inks, it’s a good idea to clean your pen thoroughly to avoid mixing colors. And if you’re using a pen with a converter, you can test different inks without committing to a whole cartridge.

• Converters let you use bottled ink; cartridges are more convenient for travel.
• Many pens accept both, so you can mix and match.
• Clean your pen between ink changes to avoid color mixing.

Step-by-Step: Filling Your Fountain Pen with a Converter

1. Prepare your pen: Clean and dry your pen to ensure no old ink residue interferes with the new fill. Checkpoint: Run water through the nib and feed until it runs clear, then dry thoroughly.
2. Insert the converter: Push or screw the converter into the pen's section until it fits snugly. If it doesn't fit, you may have the wrong converter type. Mistake to avoid: Forcing the converter can damage the pen or converter.
3. Dip and fill: Submerge the nib completely in the ink bottle, then expel air from the converter by twisting the piston or squeezing the reservoir. Release to draw ink up, repeating until full. Mistake to avoid: Filling too fast can cause air bubbles and a partial fill.
4. Clean up: Wipe the grip section with a tissue or cloth to remove any excess ink before reattaching the barrel. Checkpoint: No ink should be visible on the outside of the pen.
5. Store and use: Keep your pen nib-up or horizontal when not in use. If you notice ink starvation, your pen may need a gentle shake or a few minutes to let ink flow to the feed. Mistake to avoid: Storing pen tip-down can cause leaking and ink pooling in the cap.

Products That Pair Well with Converters

• Leather Zippered 3 Slots Pen Case - Navy Blue: Holds up to 145mm (5.70 inches) sized pens, has 3 pen slots, a credit card or ID slot, and is made of full grain leather with a YKK zipper. When you carry a pen and converter, this case keeps your writing tools organized and protected from scratches and leaks.
• Diamine Flower Burgundy Rose Fountain Pen Ink: Brand: Diamine, Type: Bottled Ink, Name: Burgundy Rose, Color – Shading, Dry Time: 30 seconds, Bottle Material: Glass, Volume: 30 ml, Origin: England. This bottled ink is exactly what a converter is designed to use, letting you fill your pen with a rich, shading color that isn't available in cartridges.
• Teranishi Guitar Taisho Roman Haikara Ink - Innocent Mauve: Brand: Teranishi, Type: Bottled Ink, Name: Innocent Mauve, Color: Purple, No Shading, No Sheen, No Shimmer, Dry Time: 35 seconds, Bottle Material: Glass. A unique bottled ink that gives a consistent, true color—perfect for converter users who want a reliable, no-shading ink for everyday writing.
• Leather Zippered B6 / B6 Slim Planner Folio - Crazy Horse Brown: Made of 100% vegetable tanned cowhide, craze horse finish, measures 8.26 x 6.29 x 1 inches, ages and softens quicker than regular leather, suede feeling finish. A folio like this is ideal for carrying your pen, converter, and a notebook together, providing a dedicated spot for your writing setup while on the go.

Using a converter in your fountain pen is simple once you know the steps. It opens up a world of bottled inks, saves money, and reduces waste. With a little practice, you'll be filling your pen like a pro in no time. And when you're ready to carry your pen, consider a leather pen case to keep it safe and stylish.