All About Eyedropper Fountain Pens

Eyedropper conversion for fountain pens is something that is talked about often in the pen community but can be hard to learn for new fountain pen users. The term might be confusing, and manufacturers often don’t advertise this filling option on their pens, so it’s usually more experienced pen users that get to enjoy this pen capability.

In this article, we aim to make eyedropper fountain pens less mysterious, and teach you how to do your own eyedropper conversions!

What is an Eyedropper Fountain Pen?

An eyedropper fountain pen is a fountain pen where you can fill the entire barrel of the pen with ink. Some fountain pens are built with this as the primary filling mechanism; others are cartridge/converter pens that can be "converted" to an eyedropper-fill.

What are the benefits of converting your fountain pen to an eyedropper?

Massive ink capacity! Since you're able to fill the entire pen barrel with ink, you can fit soooo much more inside.
If you're using a demonstrator (clear/translucent) pen, you'll get a pleasing visual effect seeing the ink slosh around in the pen.
It can be more cost-effective since you aren't relying on cartridges or converters, or having the cost of a complex internal filling mechanism built into the original pen's price.

What are the drawbacks of converting your fountain pen to an eyedropper?

Can be more complicated for filling (using an ink syringe or an eyedropper instead of directly filling the pen from bottled ink).
More likely to leak/burp due to the large ink capacity and more air inside the barrel when the ink level gets low.
Cleaning is more involved since the ink can really get all up in the pen.

Why do eyedroppers have more of a tendency to burp ink?

It all has to do with air pressure. The higher the pressure in the pen, the more burping you’ll see. The increased pressure comes from heat buildup (often from your hand while you’re writing). Eyedropper pens almost always have higher ink capacities, and when the ink level gets below half, you might see burping start. Where the pen rests in the crook of your hand (where the most heat comes from) is right on the air pocket in an eyedropper fill, but is behind the piston seal in a piston pen. That’s my theory at least! Check out more of my thoughts in the video below:

Which fountain pens can be converted to eyedropper-fill?

One of the most popular fountain pens to convert to eyedropper-fill is the Platinum Preppy. It's a very affordable pen, and eyedropper conversion is far cheaper than purchasing a converter or ink cartridges.

The Noodler's Ahab has a built-in piston mechanism, but it can also be removed and used as an eyedropper pen for a massive ink capacity of over 6ml!

Edison pens can be converted as well by removing the cartridge/converter.

The Kaweco Sport is a pocket pen that normally takes short ink cartridges or a mini converter, but converting to eyedropper greatly increases the total ink capacity.

Maiora also makes several fountain pens that are eyedropper-able.

Finally, there are some pens that are made just as eyedropper-only pens, like Opus 88 or the Namiki Emperor.

Opus 88 clear fountain pen and eyedropper

How to Convert a Fountain Pen to Eyedropper:

Supplies needed:

Silicone grease at a minimum.
O-rings (ideally). Platinum Preppy O-rings work with most fountain pens; they measure 10mm diameter by 1mm thick.
Ink syringe, disposable pipette, or a glass medicinal eyedropper.
A paper towel (it can be messy!).

Steps:

Take the pen apart between the grip and body. Remove the cartridge or converter.
Dab a tiny amount of silicone grease on your finger, toothpick, or q-tip and spread silicone grease on the threads between the grip and body.
Fill the pen body with ink up to the threads, but not quite the top.
Screw the grip back onto the body and set the pen aside to allow the ink to work through the feed, or "shake it down" through if you're in a rush.

How to Clean an Eyedropper Pen

Dispel excess ink from the pen.
Fill the pen body with clean water, shake pen lightly to help remove excess ink.
Dispel water from the pen body back into the sink.
Blot the pen body dry with a paper towel.
Run water through the pen grip and feed.
(Optional) Fill a bulb syringe with water and insert into the back of the grip section. Flush water through the grip, into the sink. Repeat until the water runs clear through the pen!
Gently blot dry the nib/feed/grip section with a paper towel.
Dry and reassemble your clean eyedropper pen!