How to refill a fountain pen ink cartridge from bottled ink.
https://shuttersparks.net/refilling-fountain-pen-ink-cartridge/
@shuttersparks I refill my cartridges, too, and prefer them to converters. But I’ve recently had several refilled cartridges fail — they won’t stay connected to the feed. Have you had this happen? How many times do you typically reuse your cartridges?
@LGsMom That depends. I handle carts that I intend to refill very gently. I refill internationals and Sheaffers. (I'm a Sheaffer school pen nut.)
I've found that it depends on the individual cartridge. Some fail quickly, probably because the plastic "tears" poorly. But most last me a very long time.
I have Sheaffer carts that I've been refilling over and over for years. But I'm very gentle about pushing the cart onto the nipple. I don't drop the cartridge into the barrel and screw the section on like you do with a brand new cart. I carefully plug the nipple into the cart by hand, with a little twist, then slip it into the barrel. That may make a difference.
@shuttersparks Thanks. I mostly use Kaweco sports bc I love how light they are in my hand and always press the cartridge into place but will try being more careful in the future. I don’t think the cartridges are as sturdy as the Schaeffer and Pilot that my husband’s pens use so maybe it’s not just my technique.
@LGsMom Hmm, I dunno. Just bear in mind that cartridges are not engineered to be used more than once. You're supposed to use them and throw them away. So I always feel lucky I can refill them at all so I'm very careful with them.
I don't think I've ever had one of the old Sheaffer school pen cartridges leak even after many refillings. I have had some internationals fail, though.
If you're really serious about capacity, Sheaffer school pens can be easily used as eyedropper fill. All you need is a little silicone grease to put on the threads of the feed. Fill the whole barrel with ink and screw it on. No cartridge. Works great. I wish I'd known that when I was a kid, too. That's a ton of ink capacity. For this I prefer the 1950s vintage school pens.
Now with the TWSBI pens I no longer do that. They have enough capacity to get me through days of writing.
@shuttersparks We have a couple of twsbis between us. I really like them but I love my Kawecos more. I’m not so concerned about capacity that I’d want to convert my pens to eyedropper fill it’s just that the Kaweco converters don’t hold as much as their cartridges plus I hate to toss things if I can reuse.