Posted in Pens, Stories

Fountain Pen Primer 103: Ink Reservoirs

An ink reservoir is what makes a fountains pen a fountain pen.

They come with a choice of two types of reservoirs: removable – being cartridges and converters or permanent – include eyedropper, piston, vacuum, and sac. Each have their own unique pros and cons.



These are pre filled with ink and are disposable. They are relatively expensive compared to bottles of ink and the choice of colors is limited. Yes you can cheat (assuming you have a syringe) and want to go through the challenge of self filling the cartridge with the ink of your choice.

These are the easiest to replaced, simply unscrew the section from the barrel, pull the now empty cartridge out and insert a new one. They come in various lengths so make sure the one you choose fits your pen.


Assortment of Converters

Converters are essentially replaceable cartridges and we can fill with whatever ink (never India ink) we choose. Some converters screw into place, while some push in like a cartridge. Like cartridges, they also come in a variety of lengths so make sure the one you choose fits.

Filling a converter is accomplished in a couple fashions. My preferred method, install the converter, engage the fill mechanism to depress the plunger. Dip the pen into the ink, work the mechanism again. As the plunger retracts it creates a vacuum and draws ink into the converter via the nib. It can be a messy process as you have to clean the nib afterwards but the pen is ready to use. The alternative process is just like the previous except before the converter is installed you stick the open end of the converter into the ink directly then engage the mechanism and draw in the ink. Lastly, using a syringe is another option and makes a clean alternative to filling a converter.




Essentially, a fixed converter that uses the inside of the barrel as the reservoir. Twist the filling mechanism left or right to transition the plunger in the barrel. To fill, place the nib in ink and rotate the mechanism clockwise. This retracts the plunger and draws ink into the barrel. This type of reservoir is difficult to clean. On a side note, this filling system was patented in 1923.


Parker Vacumatic

A Parker proprietary design mechanism. The inside of the barrel is the ink reservoir, a plunger mechanism with a diaphragm is locate at the opposite end from the section. When the plunger on the mechanism is depressed it expands the diaphragm, expelling air. When released the diaphragm retracts and ink is drawn into the pen. To fill the pen simply insert the nib into a bottle of ink, press the plunger and release, ink fills the pen. This type of reservoir is tiring to clean. On a side note, this filling system was patented in 1933.


Esterbrook J series

Ink sacs are mostly found in vintage pens and the occasional contemporary. The sac is attached to the section and when depressed by a filling mechanism, the air or ink is expelled from the sac. When the mechanism is released the sac expands and draws in ink. Common filling mechanisms associated with a sac reservoir include a Lever, Crescent, Areometric, Button, and Leverless. This type of reservoir does not clean well.


Wality Airmail

Makes use of the entire hollowed area of the barrel as a reservoir. The section is removed thus providing access to the reservoir. The threads of the section are usually sealed with a silicon grease or an o-ring to keep the pen air tight. To fill, remove the section then using an eyedropper extract ink from a bottle and squirt it into the barrel. Filling the pen requires care as one slip, the pen falls and ink flows everywhere. It is by far the easiest to clean and provides the highest capacity reservoir.


I'm a loser as my wife likes to tell me, I enjoy researching dead cousins and playing with fountain pens.

8 thoughts on “Fountain Pen Primer 103: Ink Reservoirs

  1. Great explanation. As you said, cartridges are expensive and filling them seems to be an option. With a plethora of bottled fountain pen inks available and in many different colours? I suppose it can give a greater choice other than the limited cartridge colour choices. Also. Recycling plastic would be eco friendly too. Cheers for this subject knowledge and enlightenment.


  2. The cartridge, converters, pistons and sac with twist or lever fill are familiar. But the vacuum and eye dropper ones are new to me. Heard them mentioned here and there but never looked into how they worked. So cheers. You might be interested in the Rotring/Pelikan Graphos filling method. Not a fountain pen that is a familiar writing tool. But they have writing nibs as well as art nibs. Messy! But the ink flow 1,2 and 3 interchangeable inserts are interesting.


    1. Eyedropper pens are very common in Asia because of the effects on the ink by the heat and humidity. A YouTube search will yield ways to convert a cartridge style pen to an eye dropper. I have a couple, 2 vintage Gold Starry pens (they have retractable nibs) and 3 contemporary pens from India.


      1. Cheers. Will look into them. My site here has been brought to life by my son’s partner. Before I wrote, uploaded and it was all of a ‘toilet roll’ keep scrolling down design. Now I’m improving my methods of how to access others’ blogs. Alongside other contributors, found your older posts too. Be good to catch up with posts from others over the weeks and months. Some great advice. Read a Ylang Ylang aromatherapy oil post and your Worth pen insights this morning. As a nurse I have always sought information. Helps avoid the problems and also gives impetus to having interests tweaked and looking for yourself too. My wife has a Wholefood Shop, my daughter is a fine photographer, my son is a wine expert, his partner an organic inspired gardener and my daughter’s partner a podcast contributor regarding film critiques. Love the fact that all these interests can be pursued a little and discussed. So cheers. 👍


      2. I have stumbled and fumbled my way through WordPress. I work in IT but still found it very difficult to use. Fortunately, I know enough HTML so I could make it work for me. In the States, the first week of May is National Nurse week so I am planning a post on “nurse pen” sets. I have an Esterbrook set to highlight – I hope you will find that interesting. My daughter is a Peds ED nurse for 13 years. Seems like forever. My son is a dietician/chef in a nursing home for Aids patients – he is a better man than I.

        BTW I loved your Ray-Ban post

        Liked by 1 person

      3. Cheers. Nursing for the last 2 years in COVID was intense. At 65 y/o I could consider the NHS pension options. So bit the bullet. Have a 1/5 of my old income, but my spirits are much improved. Your children must be troopers. You must be very proud. Both their jobs are inspiring. I wrote with a fountain pen in patients’ notes and it was easier to be honest. The flow mainly. My son’s partner did a course way back in computer studies so polished off the building of the site double quick. Myself as a technophobe? Needed the help. RayBans are cool as cool. I dress for my age, but love bohemian vintage scruffy. Look forward to your post. I’m lining up the Graphos nibs and pens for a future post. All the best. 👍

        Liked by 1 person

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