Occasionally I’ve encountered topics on the FPN about diluting fountain pen ink. I ignored the topics assuming it was a solution to address a problem when the bottle of ink has evaporated – fountain pen ink is water-based.
Fountain pen inks are sold as “out of the box, ready for use.” That doesn’t mean they aren’t viscous (resistant to flow). Thick ink clings to the nib, causing havoc with the capillary action. This can also happen to older inks, or high pigment inks, or have been exposed to long periods without a lid on the bottle (yes I have done this), resulting in significant water evaporation.
Other than poor performance low viscosity means longer drying time. This is especially true for those who reside in places with high humidity (not a problem for me). This leads to inconsistent pen strokes and blotchy letting. If left unattended, the ink will clog the pen rendering it unusable.
Solution? Adding a little distilled water to the ink will improve its fluidity. Do this in moderation, don’t add the water directly to the bottle. You may accidentally over dilute and the ink will be ruined.
Bonus: this may also be an option for the lefties as diluted ink dries faster.
Other than your favorite vintage pen author left a bottle of ink open for a week, why else would one dilute fountain pen ink:
- To decrease ink drying time,
- To improve the wetness of the ink,
- To prevent clogging,
- To lighten the color of the ink,
- To revive ink due to water evaporation,
- To stretch a bottle of ink further (inflation-fighting solution),
- To decrease page see-through (ghosting).
How to Dilute Fountain Pen Ink
Begin by decanting a small amount of ink using a syringe into an ink sample bottle, then introducing a small amount of distilled water; a 2-to-1 ratio of ink to water is a good standard. The water must mix completely with the ink so shake don’t stir the mix. Afterward, it should not separate, if it does, there are impurities in the water, and you should restart the process using fresh materials.
As fountain pen users we all know the same ink behaves differently between pens and paper. It is important to consider the pen using the diluted ink, the paper, and your climate conditions (humidity). Flex nibs can benefit from a more diluted (less viscous) ink, while a stiff/rigid nib can use a less diluted ink.
If the ink needs to be less viscous, add more water (2-to-1.5); if you prefer a diluted ink that is more viscous and with better saturation, add more ink (2.5-to-1).
How Much
Since we are talking about small amounts of liquid I will express quantities in milliliters. For a less diluted ink (closest to the original ink), mix 45 ml of ink with 10 ml of water (4.5-to-1). For an extremely diluted ink (minimal viscous) mix 2.5 ml of ink with 0.5 ml of water (5-to-1). A safe diluted ink mix ratio mix of 20 ml of ink with 10 ml of water (2-to-1 ratio) will satisfy most fountain pen inks.
- Do you dilute ink?
- Why and is it working for you?
I have an ink busy evaporating for experimentation with dilution – more on that another day.
Reference Material
- Endless Pens; How to Dilute Fountain Pen Inks
- Art of Scribing; Can you Dilute Fountain Pen Ink
- Art is Fun; How do you dilute ink, Are you supposed to dilute ink
- The Postman Knocks; Why, When and How to Dilute Ink
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I wondered when someone would get around to commenting on the subject of evaporation of ink! The more careless among us are familiar with the saturation this produces. I once put my beloved Hero 330 (full of Noodler’s Walnut—a MAGNIFICENT pairing, by the way) into a box that was packed away for at least six months. The ink didn’t dry completely, but became so saturated that drying time was overnight. The result was the most beautiful mahogany brown I’ve ever seen, and the letters could literally have been read by a blind person if written in Braille. Although the ink was close to being paint, the writing was not impaired in the least. I have had that pen close to eighteen years now, and cleaned it maybe once. Those ultra-cheap Hero pens are as reliable as an AK 47. Parker wanted to manufacture pens in China in the early seventies and sent some machinery over (I had read somewhere), so they’re not necessarily total knock-offs. I purchased a nearly identical Soviet-era pen from a Hungarian seller on eBay, so China was selling them into Eastern Europe in the seventies.
Diluting ink with distilled water is not something I would do, but I have experimented with evaporation in a lab oven. Personally, I have been leaning toward mixing a 10% weight of Black ink into N’s Walnut to produce a darker brown, but nothing beats the extraordinary color of the supersaturated ink in that pen. My most memorable pen & ink experience! (Yes, I lead a boring life.)
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Supersaturation… I should have added that as a point-counter-point discussion. Browns are my favorite color, the darker the better. I am allowing a small amount of de Atramentis Chianti to evaporate. It is a dark red, leads one to assume the pigment count is high which should produce a nice supersaturated ink. Hmmm, sounds like a blog topic. Thanks for the insight and the idea. All the best.
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Dilution is something that is sometimes recommended for high saturation inks like Noodler’s. I’ve heard of it being diluted 50% before significantly changing the color. But, ymmv.😁
I’ve used an Esterbrook 407 inkwell and a Dip-Less dip pen. Technically open, except for what the pen holder fills. (Glass container got flipped upside-down and there’s a cap and a gasket. Opening for the pen is about it.) They hold 2 ounces, and with business levels of use, in the past, they lasted 2 months. Today, you end up adding some water, unless you like a darker color.
A big thing about evaporation is that there’s a higher risk of “SITB,” or “stuff in the bottle,” exposed to air. Molds and the like, especially with low fungicide inks, especially from France (they ruined the growth inhibition by legislation.) Gone are the more aggressive fungicides, like phenol. Most are still pretty resistant, but the risk can be increased.
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SITB is my biggest concern, hence the distilled water recommendation. I’ve been fixated on vintage inkwells as of recent, in part with diluted in mind. I have also been toying with the idea of making my own ink but only use that in an inexpensive nearly disposable Chinese pen. Thanks for the comment. All the best.
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