The biggest advantage of converting a fountain pen into eyedropper fill is the huge reservoir of ink! No need for converters or cartridges, the whole barrel is full of ink. It’s easy to clean out the barrel when you want to change ink colors or want to store your fountain pen. If you’ve got a transparent pen and colorful ink it’s especially fun to use!
Fountain pens can be converted to eyedropper fill as long as they do not have any holes in the body for the ink to leak out of or are not made from special materials that would be harmed by direct contact with ink or silicone grease. Some pens are better suited than others for this conversion because the design of the area where the feed and the barrel screw together can affect how well the pen seals.
However, modern fountain pens are not designed to be eyedropper fill pens, and because of this there are some problems to be aware of. Even when these pens are sealed correctly with silicone grease and/or rubber O-rings, they are still prone to leaking.
When there is heat, the air inside the pen can expand forcing ink out of the nib or from the seal creating a big mess! Due to this problem it is often necessary to refill your eyedropper pen when it gets to about 1/3 full of ink. In my case, I have hot hands and have to refill my pen when it gets to 1/2 full, otherwise beads of ink start dripping out of the nib spoiling whatever I’m writing on. If you carry the pen in your shirt pocket you could experience the same results. I’m unsure of how much hot weather is a problem because I live in Portland, Oregon where it rarely gets really hot. Does anyone have personal experience with this? If so, please share by leaving a comment!
Air travel can produce the same undesirable results as heat – as the air pressure changes in the cabin of the plane, the air inside the pen expands and can force ink to leak out of the pen. This is why I never take eyedropper fill pens with me when I’m travelling by air. In fact, I do not travel anywhere with my eyedropper pens! They sit on my desk, nibs pointing up, to be used where I can easily do a clean-up in case of ink leakage.
In my case, the possibility of having an ink leak and having to keep the pen at least 1/2 full of ink offsets the benefit of having a large ink supply in the barrel. I only have access to 1/2 a barrel of ink at a time anyway before it starts to leak. Sure, it’s easy to see the level of ink and know when you have to refill if you have a transparent pen, but what about pens that are not transparent?
With all of their disadvantages, many people still find that eyedropper pens are a nice alternative to traditional piston fill, converter or cartridge fill fountain pens. What are your thoughts and experiences with using eyedropper fill fountain pens?
Previous blog posts about eyedropper fill fountain pens:
Pen modification – convert into eyedropper fill
Should you use an O-ring to convert your fountain pen into an eyedropper?
When should you refill your eyedropper pen?
Is it safe to take a fountain pen on an airplane?
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Hi. I hope this isn’t a really stupid question, but would you fill a non eyedropper pen with “eyedropper ink”? Is that ink suitable for pens non-ED? For example, use a Noodler’s Nikita (or the one in the picture of this article) with a FP with converter. Thanks and best regards.
Yes, you can use the Noodler’s inks that come with eyedropper pens in a fountain pen with a converter. These inks are designed for use with a regular fountain pen but can also be used with eyedropper pens. Noodler’s has been including a bonus eyedropper pen with some of their ink, but you’re not limited to using the ink only in the eyedropper pen that comes with it.
This may sound really silly but how would you refill them?
Just open it up and fill or would it be able to draw some up using normal capillary action?
Hello Vivek,
Not a silly question at all. Generally these type of pens are refilled by unscrewing the nib section from the barrel and then using an eyedropper full of ink (or something similar) to put ink into the barrel. The Stipula Bon Voyage eyedropper fountain pen even includes an eyedropper for refilling: http://shopwritersbloc.com/stipula-bon-voyage-fountain-pen-opal-medium-nib.html