Pens and Pencils | Reviews and Data

How to Refill a Fountain Pen Cartridge

Lamy T10 Cartridges
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It’s a popular question: Can I refill a fountain pen cartridge? The answer is a firm yes! You can, and you should. This reduced your use of plastic and can save you lots of money.


You need very little in the way of materials:

This method makes use of a blunt-end syringe in order to refill the cartridge. This is necessary because the hole at the end of the cartridge is quite thin and fountain pen ink is slightly viscous so refilling through any other means (an eye dropper for example) is not possible.

The first thing you need to do, before any other step, is to inspect the cartridge you plan on refilling. Look for any visible cracks or wear. It’s unlikely you’ll find anything, but in the case that you do you’ll want toss the cartridge and use another. The most obvious place for wear will be at the end, where it connects with the pen. Cartridges are pretty tough, so there isn’t much to worry about, but there is no use saving a few pennies but then ruining a shirt or bag.

Filling A Cartridge

Once you are underway, you’ll want to remember one important thing: fountain pen cartridges are very small! A standard short international cartridge holds a bit under 0.7 ml of ink, where a typical fountain pen syringe or pipette hold 4 ml. So don’t fill up your syringe and then give a firm push into your cartridge because you’ll create an ink volcano.

Also, don’t fill your cartridge all the way, like they do in the factory. New cartridges are sealed so they can be pushed on without ever leaking because the push action breaks the seal and instance reseals the cartridge. A good mark to shoot for is about 90% full.


What is the capacity of a standard international short fountain pen cartridge?

These standard, nearly-universally used and widely available cartridges have a capacity of 0.7 ml but are normally filled to around 0.65 ml.