Reloadable Cartridges

[ek-hornbeck]

I always grumble a little bit when I have to use a pen that uses cartridge converters to handle bottled ink. The problem is that the capacity of these converters is so small. They are a pathetic bit of technology, when one is used to piston-filler pens. I wish someone -- perhaps Nathan Tardif at Noodlers -- would make refillable, sealable cartridges for pens that take standard, international-cartridges. (Uh... and also for Platinum, Parker and Pilot format cartridges.)

What I'd want is something like Tardif's "308" refillable cartridge that Noodler's provides for its Ahab and Neponset pens, but in an international-cartridge format. That is,

• made of strong, solid clear plastic;
• threaded for a cap that can securely seal a full cartridge when it is not being used inside a pen; and
• available in a range of lengths from very short to very long, in increments of 1 mm.

Such a cartridge would roughly get you double the capacity of standard piston cartridge converters, because all of the pen's barrel length would be used to store ink; none would be needed for the piston mechanism. You could buy one in a size that would use as much barrel length as your particular pen provided -- short for a Pilot Elite 95s, long for a Sailor King of Pen. (This is especially critical for short pens -- they desperately need the extra capacity.)

But why buy just one? Buy five, fill them with a syringe or an eye-dropper in your office, and carry them around in a screw-top plastic cylinder for safety. Now your ink problem is completely solved, when you are out & about.

For extra points, line the interior of the cartridge with a thin layer of teflon (better yet, aluminium magnesium boride). Now you will have no capillary forces keeping ink stuck at the rear of the pen; it will all flow downhill into the feed. You can afford the extra expense of doing so, because these cartridges aren't disposable. So this will be a much better ink-reservoir system than either standard converters or cartridges. A thin layer of Teflon will suffice, because the interior of the cartridge is not a high-wear surface -- and a thin layer is good, because you want the walls of the cartridge to be as transparent or translucent as possible, so the ink level of the cartridge can be visually seen.

(In a similar vein, I wish that makers of piston-fillers, like Pelikan, Montblanc, TWSBI and Sailor, would teflon-line the reservoirs of their pens. Not only would it improve ink flow, but it would improve the efficacy of flushing the pen with water to clean it, e.g., when changing inks.)

I would pay $20/cartridge for such a thing. And I'd buy a bunch of them. They'd completely alter the useability of cartridge/converter pens for me.

E. K.

P.S. Alternatively, how about a piston-filler converter with a detachable pushrod/plunger? To refill the pen, you screw the rod into the back of the piston, do the refill, unscrew and detach the rod, then recap the pen. Make the piston long for stability in the converter barrel, and have the rod screw into the back of the longer piston. Simple and not particularly high-tech, but you ought to get close to a 2x multiplier in filler capacity over the current designs.

[ac12]

How much ink do you use during the day?

 

Your cartridge mouth will wear over time. Just as a refilled cartridge only has so many insert/remove cycles, so would your cartridge. Unless you plan to make the mouth out of a flexible sealing material = more cost.

 

A cartridge or converter in increments of 1mm length is commercially economically impractical. And the inventory cost of someone stocking them would also be economically impractical. Maybe 2 lengths; short and long international.

 

How is Teflon applied? I've only seen it on metal items, not plastic.

 

The converters that I have taken apart do have the inner shaft going into the outer knob, so there is already the overlap you are talking about. The issue is the length of the piston shaft, which has to be at least as long as the piston travel distance + a bit more.

 

A cartridge converted to a bulb filler would give you the added capacity that you want. I did that with an international cartridge for a pen that none of my international converters would fit. It worked just fine.

[cattar]

For $20, consider a glue gun or a lot of candles or wax. Use that to reseal cartridges you've refilled. That's what I do for shorter trips.

[Komboloi]

For $20, consider a glue gun or a lot of candles or wax. Use that to reseal cartridges you've refilled. That's what I do for shorter trips.

 

@cattar, I've thought about the glue gun idea before, but I figured the glue wouldn't adhere reliably to the mouth of the cartridge, would be difficult to remove if it did adhere, or would melt/deform the mouth of the cartridge.

 

No problem? You've done this to good effect and traveled with such resealed cartridges? Any tips for application of hot glue -- where and how much, for example? I wouldn't mind using this technique to keep a supply of custom-loaded carts around.

[cattar]

For no heat - could use silicone sealant/caulk from a hardware store. Be sure to peel it off before using the cartridge.

 

Others on the board wrote about using a glue gun. I've used them for set building so I know they're hot enough to liquify the glue stick & that the hot glue cools/dries quickly & is easy to peel off hard surfaces.

It'd probably be easier to use than wax.

 

I light a tiny candle & drip a blob onto the cartridge. Heat deformity hasn't been a problem. Later, I flick off the wax & put the cartridge on the pen.

 

Be sure to place the cartridges in a sealed container so the temporary closure doesn't get peeled off by movement in a bag.

[Bo Bo Olson]

Solid piston pens are first choice.

I find any cartridge too expensive....even if made to be refilled like some sort of bigger converter.

 

So one can needle refill or converter refill or own two piston pen.

If one writes so much that two piston pens can go empty.....I would expect one to have a permanent desk with a lockable drawer for a jar of ink.

 

One can get a nice nibbed used 200 for about $50....that and the CC pen and you are good to go.

[ek-hornbeck]

How much ink do you use during the day?

Less than even a crappy, international-standard cartridge contains. Unless, that is, I'm locked in a room on in an all-day death-march grading tests for a 400-student course, which happens to me about twice a year. I blow through red ink like you wouldn't believe. But that's not the point. How much gasoline do you use in a day, as you drive around? Why do you want a gas tank for your car that's larger than that?

I don't want to run out of ink when I'm away from the bottle of ink I keep in my office. But I don't want to carry around said bottle. Nor do I want to have to take the time and trouble to refill my pen every time I get ready to leave my office to spend an hour or two at a coffee shop. Just because I don't run out every day doesn't mean it's not going to happen to me today. First, doubling the capacity of my pen lowers the odds that I'm going to run out on a given day. Second, the mode of having one spare in my daypack means that if I do run out while I'm sitting at a cafe, I have another entire double-sized load of ink to last me from that point until I am next in my office.

This goes double for travel. Besides conferences and meetings ordered by my grant sponsors, I routinely spend a few weeks every year unplugged and detached somewhere nice in Europe, just me and some problems I'm kicking around, and a pen and a pad of paper. A full 1.5-2 ml cartridge in my pen plus one spare would likely get me through a week on the road. Especially since these things, again, are each twice the capacity of the standard cartridge converters. And one or two spare carts is a lot less to travel with than a whole bottle of ink.

Your cartridge mouth will wear over time. Just as a refilled cartridge only has so many insert/remove cycles, so would your cartridge. Unless you plan to make the mouth out of a flexible sealing material = more cost.

Then stop thinking of this as a cartridge and start thinking of it as a syringe-filled cartridge-converter. Cartridge converters do not seem to have the problem you describe above, no? As for "more cost," I'm assuming we spend more money making this thing that is spent on standard cartridge converters. It's a better product -- it holds more than a regular cartridge converter, and lets you use the ink of your choice, unlike a regular cartridge -- so it commands a higher price.

A cartridge or converter in increments of 1mm length is commercially economically impractical. And the inventory cost of someone stocking them would also be economically impractical.

Possibly. But I'd have to see the numbers. The only manufacturing difference is the length of the plastic barrel. I think it would be easy to make a range of lengths. If you made a range from, say, 50 mm to 76 mm, in 2mm increments, that would be 14 sizes, covering the range from the length of the wretched Kaweco Sport converter up to the Pilot Con-70. Go long two more, to cover your bases, for 16 sizes, up to 80 mm. Sure, some will sell better than others. Use that sales feedback to drive resupply. It's not as if aging stock is going to tie up much money or storage space.

Better still, on the product web site, have a table showing the right max lengths for various popular pens. You don't even have to work it out; have a little web forum and let your customers post the right answers. Have an intern mine it out once a month for updates to the official table.

How is Teflon applied? I've only seen it on metal items, not plastic.

I have no idea. Note that Teflon is a plastic -- essentially polyethylene's sullen, detached cousin.

For $20, consider a glue gun or a lot of candles or wax. Use that to reseal cartridges you've refilled. That's what I do for shorter trips. For $20, consider a glue gun or a lot of candles or wax. Use that to reseal cartridges you've refilled. That's what I do for shorter trips.

Yep, that's the field-expedient DIY solution. But you have to re-use disposable cartridges, and these -- as ac12 observed -- aren't really designed for long-term reuse.

E. K.

[cattar]

I get 40-50 re-uses from a cartridge. Yes, I keep track.

If you develop a specially manufactured reusable cartridge that lasts longer, I might be interested. It'd have to cost less that a pack of cartridges with ink, and last longer than 8 years.

[ek-hornbeck]

I get 40-50 re-uses from a cartridge. Yes, I keep track.

If you develop a specially manufactured reusable cartridge that lasts longer, I might be interested. It'd have to cost less that a pack of cartridges with ink, and last longer than 8 years.

 

You're a tough customer, cattar.

[cattar]

I want value, as well as aesthetics, in a product.

Didn't know carts would last so long until I started reusing them.

[Jamesbeat]

1mm or 2mm increments:

Most pen manufacturers worth their salt (and who use international cartridges) make their pens the correct length for a long cartridge or two short cartridges back to back.

I'm sure there must be pens that are exceptions, but that's a niche market.

Any idea how much an injection mold costs? They are very expensive.

 

Cartridges are made of LDPE, which while not as slippery as PTFE is slippery enough to insure good ink flow.

Teflon is just not necessary because the added cost would not increase performance appreciably.

 

The screw on cap is a good idea, but how would you implement it and still end up with a cartridge that is compatible with the international standard?

 

I gave this some thought recently.

If you made a container that was basically shaped like the inside of a pen, you could insert a filled cartridge for storage.

The nipple would be solid instead of hollow, and would thus act as a plug.

The only downside is that the opening of the cartridge would wear out faster, but they last a long time already and are cheap to replace.

[ek-hornbeck]

I gave this some thought recently.

If you made a container that was basically shaped like the inside of a pen, you could insert a filled cartridge for storage.

The nipple would be solid instead of hollow, and would thus act as a plug.

The only downside is that the opening of the cartridge would wear out faster, but they last a long time already and are cheap to replace.

 

You might even be able simply to make this with a 3D printer. Now you just need a larger canister that would let you securely carry a couple, protected from rattling around, and with a waterproof, secure, screw-on top, in case of disaster.

 

But I'd rather have what I originally proposed.

 

As for the slipperiness of regular cartridges: they might be adequately slippery, but the standard cartridge converters are not. Pilot chucks all these tiny little metal do-dads into their converters to help break capillary lock; teflon-lining the converters seems like a better solution.

 

E. K.

[dcwaites]

Have you tried re-filling a long International cartridge?

Waterman and Pelikan make long International cartridges, and Pelikan make both their 4001 and their Edelstein carts in Long.

Start off with some nice ink, and refill from there.

[oldrifleman]

Or you could get a couple of ink sample bottles, fill them with your favorite inks and keep them in your bag. That way your may refill at will.

[Jamesbeat]

 

You might even be able simply to make this with a 3D printer. Now you just need a larger canister that would let you securely carry a couple, protected from rattling around, and with a waterproof, secure, screw-on top, in case of disaster.

 

But I'd rather have what I originally proposed.

 

As for the slipperiness of regular cartridges: they might be adequately slippery, but the standard cartridge converters are not. Pilot chucks all these tiny little metal do-dads into their converters to help break capillary lock; teflon-lining the converters seems like a better solution.

 

E. K.

I completely agree about converters- different type of plastic and much worse performance, but we're talking about a cartridge in this case.

Why not just make the cartridge out of the same plastic as a regular cartridge? It works really well.

 

LDPE being nice and soft probably helps with the longevity too. I expect a harder plastic would not last as many cycles before starting to leak.

[ac12]

re in capacity.

- In college I carried 2 Parker 45s. When one ran out of ink or stopped writing, I simply switched to the 2nd pen.

- At home or in the office, an ink bottle is right there, easy to refill the pen.

- If you are traveling, just take cartridge ink.

 

re making many different sizes in 1mm increments.

- You miss the point. As James said, it is the MANUFACTURING that is where the first major hurdle is. Making 14 different sizes of cartridges means 14 different dies, one die for each length. That is a production cost and process issue compared to two (short and long). They have to sell a LOT of cartridges to just recover the cost of the dies.

- Then the stores have to buy and stock 14 different sizes. Are they really going to stock 14 different sizes? I say NO. If any it would be TWO (short and long international).

 

As for this cartridge. It is going backwards in convenience. Because you have to use a syringe to fill it, it is more inconvenient to use than a standard screw piston converter. So really how many customers are they going to have that will buy it? Most fountain pen users as it is, don't want to deal with ink bottles. So take the current ink bottle users, then take a subset of that because many (like me) won't want to deal with syringe filling a cartridge. I syringe fill the cartridge for ONE pen, because I don't have a converter for that pen.

 

If you really thing this makes economic sense, why not start a business to make the cartridges.

[Jamesbeat]

Or start a kickstarter project. That would be a good way of gauging interest...

[Komboloi]

 

As for the slipperiness of regular cartridges: they might be adequately slippery, but the standard cartridge converters are not. Pilot chucks all these tiny little metal do-dads into their converters to help break capillary lock; teflon-lining the converters seems like a better solution.

 

 

I completely agree about converters- different type of plastic and much worse performance, but we're talking about a cartridge in this case.

Why not just make the cartridge out of the same plastic as a regular cartridge? It works really well.

 

I agree with Jamesbeat for the reasons ek-hornbeck expresses: Any such refillable cartridge should be made out of something other than what converters are made out of. And the more-slippery material used in cartridges would be an obvious solution. In fact, I wish manufacturers of converters made them out of the same material used in cartridges. I'd gladly give up whatever advantage there is in transparency for more reliable flow. When I open a pen that has a cartridge in it, I can see how much ink there is through the translucency of the cartridge material. Perhaps there are issues other than transparency that drive converter manufacturers to the material they use. But that material should not be used in anyone's design of a commerically-produced refillable-resealable cartridge in my view.

[Komboloi]

Here's another idea: Rather than creating a bespoke refillable cartridge, how about just creating a snug-fitting cap that will snug onto currently available cartridges? If the cartridge's inner diameter can friction fit securely to a feed, I don't know why its outer diameter couldn't friction fit securely to a cap.

[Jamesbeat]

Here's another idea: Rather than creating a bespoke refillable cartridge, how about just creating a snug-fitting cap that will snug onto currently available cartridges? If the cartridge's inner diameter can friction fit securely to a feed, I don't know why its outer diameter couldn't friction fit securely to a cap.

As I mentioned above, I think a container with a plug the size and shape of a feed nipple would work well.

What I am thinking of is a cylinder with a cartridge sized space inside. In the cap would be a rod the same size and shape as the nipple of a pen.

Inserting the cartridge into the container would be exactly like inserting a cartridge into a pen, except the nipple would have no hole in it - it would act as a plug to stop the ink coming out.

 

I may make myself one one of these days. Be handy to have on a keychain.