The Parts of a Fountain Pens: How It Works

Pen Anatomy 101

Ever wonder how a pen works? You've come to the "write" place. Knowing the parts of a fountain pen and how a fountain pen works is key to troubleshooting any issues that may occur during a lifetime of writing. Let's say you contact the manufacturer for some assistance with a problem - your pen is leaking. To help diagnose the problem, the service representative might ask, "where is the ink leaking from?" Instead of grasping for the part name, you confidently describe the pen parts and the issue becomes clear to the service representative. A simple solution is reached quickly and without having to ship the pen back. This is the benefit to knowing your fountain pen parts!

True, not all warranty issues will be an easy fix. However, an experienced fountain pen enthusiast can troubleshoot simple issues that may arise. As you'll see in the diagram below, the pen is not a complicated tool like your modern smartphone. The analog parts of a fountain pen are refreshingly simple.

We will go through eight different pens and examine their parts to understand the anatomy and design of fountain pens in-order to master how fountain pens work!

Parts of a Fountain Pen With Cartridge Fill Mechanism

The parts of a fountain pen

The Fountain Pen Nib

The nib is the heart of the fountain pen and the fulcrum of the writing experience, a critical piece of technology to understand when learning how fountain pens work. The imprint will tell you important details, such as the manufacturer and metal content of the nib. Gold nibs are struck with 14kt, 18kt or 21kt to designate the amount of gold content. A 14kt nib will have 58.5% pure gold and will often read "14kt <585>." A stainless steel nib will not have such a hallmark. Most nibs will have an engraving of the point size - EF for extra fine, F for fine, M for medium and so on. Sometimes, the nib size is engraved on the side of the nib or imprinted on the feed (Like the Aurora Optima or 88).

If your nib feels scratchy or skips while writing, you may have a nib alignment issue. To visually spot this issue, use a loupe or magnifying glass to examine the tipping material. From the front view, the tipping material should look like a sphere split in half. If both sides of the sphere don't match up, then the nib is out of alignment. Experienced fountain pen users that adjust and tune their own nibs can easily remedy the problem. If you have trouble using your pen and spot this problem, contact the shop, the respective manufacturer or a professional nib repair specialist (lovingly called a "nibmeister").

The slit of the nib carries ink from the feed's ink channel to the tipping material. Looking at the nib top-down, the width of the slit should taper from its start point at the breather hole all the way to the tipping material. Although most do, some nibs do not have a breather hole.

The Fountain Pen Feed

The feed controls the flow of ink from the main reservoir (supplied by a cartridge refill, converter, piston-mechanism, etc.) to the nib by capillary action. Feeds are designed to keep a steady stream of ink while you are writing and prevent the pen from leaking when you are not. The moment you touch nib to paper, the feed is channeling more ink to supply each stroke. The fountain pen feed determines how you will fill the fountain pen with ink.

The Fountain Pen Section

A fountain pen's section contains all the functional components, including the nib and feed. It is also the part that is usually gripped while writing. The housing is usually screwed into the section. The nib and feed are friction-fit into the housing. The fit should be snug to prevent any accidental leakage.

The Fountain Pen Barrel

The pen barrel is like the "handle" of a pen. Inside, it contains the ink reservoir, like an ink cartridge, converter, or piston-fill mechanism, etc.

The Fountain Pen Cap

The cap keeps your pen from drying out and protects the nib while not in use. Sometime's called a "lid," the cap can either screw-on, snap-on, twist-lock, or magnetically attach. Most caps have a functional pocket clip that attaches to a thin piece of fabric and prevents the pen from rolling off a desk.

Fountain Pen Ink Cartridge

The fountain pen ink cartridge is a plastic-walled ink capsule. It usually narrows at one end, where the mouth (or nipple) can be pierced by the back-end of the feed. Although cartridges are designed to be disposable, some opt to clean out and refill them using a blunt needle syringe. You can learn more about ink cartridge and converter compatibility with our guide here.

Parts of a Fountain Pen With Ink Converter Filling Mechanism

fountain pen ink converter

The Ink Converter

A converter is like an empty cartridge that can refill itself using the screw-activated piston mechanism, and is a critical component to understand to master how fountain pens work. The suction created by the piston moving from the front-end of the converter to the back will draw up the ink. Please note there are different types of converters that operate by pulling, pressing, squeezing or turning the mechanism.

Parts of a Piston Fill Fountain Pen

cap and clip of a fountain pen

The Piston-Fill Pen Mechanism

The piston-fill fountain pen operates similar to a converter, but it's important to understand how a piston-fill fountain pen works. Instead of twisting the knob of the converter, you activate the internal piston by twisting the blind cap at the end of the pen barrel. The advantage of this type of pen is a larger ink capacity over cartridge/converter type pens.

Fountain Pen - Eyedropper Pen Filling Mechanism

infographic describing how eyedropper fountain pen filling mechanism works

The Ink Eyedropper

Eyedropper-fill fountain pens utilize the entire volume of the barrel, unencumbered by the presence of an internal filling mechanism. To fill, remove the section from the barrel and use an eyedropper to transfer ink from a bottle to the pen. It would be advisable to apply 100% pure silicone grease to the section threads to ensure a leak-proof seal.
Certain eyedropper pens like the Opus 88 feature a shut-off valve that helps seal-off the ink in the barrel from accessing the feed. This feature prevents the pen from leaking due to temperature or air pressure changes.

Fountain Pen - Vacuum Fill

vacuum fill fountain pen filling mechanism

Vacuum Fill Pen Mechanism

The one-stroke filing mechanism operates using air pressure built by the movement of the piston rod. To fill, unscrew the blind cap and pull the piston back to extend the rod away from the barrel. Then, fully submerge the nib into a bottle of ink and press down on the blind cap all the way. Once the piston head reaches the forward end of the barrel, the internal pressure is released and a vacuum sends ink up into the barrel of the pen. Screwing the blind cap back in will activate the shut-off valve and seal-off the ink reservoir from the feed.

Ballpoint Pen Anatomy - Parts of a Ballpoint Pen

The Ballpoint Pen

The ballpoint pen mode utilizes a replaceable ink cartridge designed for a retractable mechanism. Most ballpoint pens can be separated at one junction of the pen. To access the refill, the writer must find how the pen can be taken apart. It is best to follow the manufacturer's directions, which are usually included in the pen packaging, or look for fountain pen accessories that might include compatible refills. If not, you will probably find a video online.

Most ballpoint pens include a spring to provide tension for the retraction mechanism. Make sure to keep the spring when changing the refill of the pen.

Ballpoint pen retraction mechanisms vary. You might twist, slide, push, or click a part of the pen to activate the mechanism.

Rollerball Pen Anatomy

The Parts of a Rollerball Pen

Rollerball pens are similar to ballpoint pens in that they use a replaceable ink cartridge. The main difference is the ink style. Where ballpoint pens use a paste ink that resists drying-out, the rollerball cartridge is liquid- or gel-based. The result is a smoother, richer, more fluid line. Since liquid ink tends to dry out and evaporate, most rollerball pens have a cap to keep the ink fresh and minimize the risk of the pen exploding due to pressure changes or evaporation.

Rollerball pens might also accept other types of refills like felt-tip, fine liner, or ballpoint type ink cartridges. Rollerball pens can be disassembled much like a cartridge/converter fountain pen. They are designed to have the section unscrewed from the barrel to access the refill.

The Parts of aechanical Pencil

Mechanical Pencils

Mechanical pencils hold a stick of graphite lead at the tip of the pencil. Most have a click- or twist-action mechanism to propel the lead forward when the tip starts to wear down. A small cone-shaped shield protects the lead from accidental breakage.

Mechanical pencils are offered in different lead diameter sizes. Please note that only one lead size is compatible with your mechanical pencil. For example, a 0.7mm mechanical pencil can only accept 0.7mm leads. Petite erasers may also be attached to the pencil. Some erasers include a small needle to help clear lead jams at the tip.

Parts of a Fountain Pen

We hope you learned a lot about the parts of a fountain pen, rollerball pens, ballpoint and mechanical pencil, as well as how fountain pens work in general.

Thank you for reading.