Most newer fountain pens use plastic ink cartridges. You can refill your own and save a lot of money. Refilling also eliminates the problem of finding the cartridge you need in stores.
Bottled ink is easy to find when fountain pens are popular, but harder to find when they are less popular. Their popularity seems to ascend every few years and then fade after a few more years. If you live near a store that specializes in fountain pens, there is no problem. Otherwise, you can order bottled ink from several suppliers on the Internet. Do not use calligraphy ink in a fountain pen.
Fountain pens have come full circle. A very early fountain pen used a glass cartridge fitted onto a rubber cone behind the nib. The user filled the glass cartridge and pushed it onto the rubber cone. Later rubber bladders and piston systems came along. Some of these got to be quite elaborate mechanically, while others were quite simple. Almost fifty years ago the plastic cartridge became popular and pens now use cartridges.
Step 1: Suitable Implements for Refilling
If you know someone who is a nurse, he or she may agree to bring you an unused hypodermic needle. They make a good tool for filling a cartridge, but you need to be very careful about sticking yourself. You could dull the needle and reduce the danger by dragging the tip of the needle on a light abrasive, like the unglazed part on the bottom of a ceramic coffee cup.
You can also get a plastic syringe with no sharp needle at a pharmacy. This have a curved end and are for washing a baby's mouth with a solution when the baby is teething.
You can also use a glass eyedropper. These are also available in a pharmacy.
All but the hypodermic needle require some modification. See the next step.
Step 2: Modify Your Implement
The plastic syringe for flushing a baby's mouth is the easiest implement to modify. You will need some thin brass hobby tubing from a hobby store. Cut it by rolling it under a knife blade as shown. You will need a piece about one inch long.
Drill into the end of the plastic syringe. Put some epoxy glue on the hobby tubing near one end and slide it up into the hole at the end of the syringe. The problem with a plastic syringe is that the rubber piston hardens in time and it becomes harder to squeeze just the right amount of ink into the cartridge.
That is why I prefer an eye dropper. But, modifying it is a little more difficult. Score around the tip of the glass eyedropper far enough from the end that you will be able to insert a piece of brass hobby tubing after the tip has been broken off of the eyedropper. I used a Dremel tool with a "green wheel" grinding stone. Hopefully, not too much glass will break away from the end of the eyedropper. Insert a piece of hobby tubing and glue with epoxy.
After a couple of years, the eyedropper may not suck ink from the bottle like it should. The rubber bulb loses its fit in time. Buy some extra eyedroppers and rob the rubber bulb from a new one.
Step 3: Filling the Cartridge
I use two hands for this task, but I also had to hold the camera for making the photo.
Do this over a sink away from dishcloths and anything that could be stained by the ink. There will likely be some small spatters, even if you are careful. They fly through the air farther than you would imagine, too. If you are married, your wife will not be pleased--not at all.
Draw some ink into your implement from the bottle. Place the thin tube into the cartridge and gently squeeze ink from the implement to the cartridge. You do not need to fill the cartridge quite all of the way to the top.
Squeeze any excess ink from the implement back into the bottle. I like to cup one hand under a running faucet and draw water into the dropper. Flush the implement out well until no signs of ink are apparent.
Step 4: Storing an Eyedropper
If you choose to use an eyedropper, you will need protected storage for it. I drilled a hole in a block of wood and insert the eyedropper. I drilled a larger hole for a short distance so part of the squeeze bulb can fit down into the block.
Step 5: A Strange Phenomenon
I got some ink cartridges at a yard sale. This Schaeffer cartridge has never been opened, yet more than half of the ink is gone. Plastic cartridges are actually porous. In time water evaporates through their walls. When you place one of these into your pen and puncture the end, remove it and fill it with water.
Some cartridge companies place a small plastic ball inside the cartridge. This can roll around and break the surface tension to keep the ink from hanging at the far end of the cartridge. They can also help to mix ink and water when the cartridge partially dried out over many years. If you want to add something to a cartridge to do this job, just cut about 1/8 inch from the end of your hobby tubing. Drop it into the end of your cartridge.
An ink cartridge will not last forever, but you can use one for a year or two before you need to replace it. You will also save a lot of money on refills for your pen or pens.
drwilloliver made it!