Looking For Pen That Doesn't Dry Out

[SoulSamurai]

Does the concept of a "half life" apply when it comes to evaporation of a fixed amount of liquid? I would assume that the rate of evaporation does not depend on the total volume of liquid, only on the surface area exposed to air (all other factors being equal of course). So if a pen loses half it's ink in three months, in another three months it will lose the other half and be completely empty, right?

 

I mean, I guess the increasing concentration of ink and increase of volume of air in the pen as ink evaporates might be factors that could vary the rate of evaporation as the volume of ink drops, but I don't know how significant they would really be.

Edited August 11, 2019 by SoulSamurai

[A Smug Dill]

Does the concept of a "half life" apply when it comes to evaporation of a fixed amount of liquid?

Not really, of course.

 

I would assume that the rate of evaporation does not depend on the total volume of liquid, only on the surface area exposed to air (all other factors being equal of course).

There's the surface area as you've mentioned, then there's some variation in pressure and level of moisture in the 'empty' space in the converter, and so on, I'd expect.

 

So if a pen loses half it's ink in three months, in another three months it will lose the other half and be completely empty, right?

I'd expect evaporation to happen more quickly when less ink remains, especially if the pen is lying on its side, because the surface area of the ink would no longer be limited to the cross-section of the converter.

 

It's going to be a non-linear function either way. However, if the cap (or entire pen) is effective at sealing the nib, I'd imagine when the space between (inner?) cap and nib-and-feed — and inside the converter — becomes saturated with vapour, further evaporation will slow down; whereas a cap that essentially allows exchange with the external environment will lead to further evaporation getting more rapid.

[ENewton]

 

Great thank you. Then this sounds like the perfect starter pen for my 13 year old niece.

 

 

I agree that a Plaisir would be a fine starter pen for a teenage girl, but I suggest buying two converters at the outset. In over twenty years of fountain pen use, I have never had any other type of converter fail--pens I've had for twenty years still have their original converters--but my Platinum converters last only a few months. Some people take converters apart regularly and lubricate them, but not everyone wants to do this, and my guess is that a 13-year-old with her first fountain pen will give up on the pen if maintenance seems unduly challenging or time consuming. Fortunately, converters are very inexpensive, and replacing the converter now and then seems to me a small price to pay for the use of these otherwise excellent pens.

[BaronWulfraed]

It's going to be a non-linear function either way. However, if the cap (or entire pen) is effective at sealing the nib, I'd imagine when the space between (inner?) cap and nib-and-feed — and inside the converter — becomes saturated with vapour, further evaporation will slow down; whereas a cap that essentially allows exchange with the external environment will lead to further evaporation getting more rapid.

 

Since we've all seen old cartridges -- still sealed -- that are less than half full, it is apparent that there is solvent loss through the cartridge plastic.

 

Since the Safari/Al-Star have open view ports, there is no chance of the barrel reaching some equilibrium of vapor...

[wallylynn]

I suppose I could use my Noodler's Ahab. I had it filled with Kung Te Cheng. After 2 weeks, it became a paste... I had to dig it out of the converter with a toothpick. (The nib and section were fine because the pen was mostly upright). A unique feature of the Ahab (and preppy) is that it can be used as an eyedropper. I filled the converter with KTC, and the barrel with tap. Voila, no more KTC paste. Worked until all the ink was empty.

 

For now, I'll start with the preppy and take it from there. maybe i'll get the wing sung for my birthday.

[A Smug Dill]

Since we've all seen old cartridges -- still sealed -- that are less than half full, it is apparent that there is solvent loss through the cartridge plastic.

 

Since the Safari/Al-Star have open view ports, there is no chance of the barrel reaching some equilibrium of vapor...

True, and I don't know whether (specifically) Lamy's converters are made of comparable material to that of which my old Pelikan 4001 ink cartridges were made. I had to throw out a whole bunch of those cartridges recently; I bought some thirty of them more than five years ago and never used any of them, and about a dozen of those were not even half-full when I checked two weeks ago.

 

However, I trust that Sailor, Platinum, Pilot (specifically, the CON-50) and Rotring converters aren't made of plastic that would allow ink to escape through their walls, based on having a Sailor Lecoule, Platinum Izumo, Pilot Custom Kaede and Rotring 400 that are still ready to write even though they were last filled no later than January this year. Whether those converters live inside a plastic, ebonite, wooden or metal barrel is, as far as I'm concerned, not a factor.

 

It could be interesting to find a spare converter of each brand, fill them fully with the same ink, and then put them side by side in a non-airtight box for six months or even a year to see how much ink remains in each, if there is some easy way to seal the different-sized mouths on the converters perfectly but without affecting their subsequent use after the experiment.

 

A unique feature of the Ahab (and preppy) is that it can be used as an eyedropper.

That's hardly unique. The PenBBS 308 comes with a factory-installed O-ring on the section threads as well as a converter, so it's ready to be used as an "eyedropper" pen with its barrel acting as a sealed reservoir. I've filled the barrel of my Sailor Profit Junior with Noodler's Blue Ghost ink and just screwed the section back on without an O-ring, and so far I cannot see any leakage from the join.

Edited August 12, 2019 by A Smug Dill

[georges zaslavsky]

Sheaffer Triumph Vac Fill or Sheaffer PFM

[BaronWulfraed]

While the main body of the converters is likely a less porous plastic than cartridges -- the mouth of said converters still has to be a somewhat flexible plastic, and that may be comparable to cartridge plastic. There is also whatever material is used for the piston itself.

[OCArt]

I have a commonplace book that doesn't get much use and on top of that we were out-of-town for 3 months. The Wing Sung 618 pen that was attached to the book wrote on the first try! The WS618 is a piston filler with a hooded nib, around $12 on eBay.

 

Here's a FPN review https://www.fountainpennetwork.com/forum/topic/326495-wing-sung-618-with-comparison-to-ws-698/

[A Smug Dill]

While the main body of the converters is likely a less porous plastic than cartridges -- the mouth of said converters still has to be a somewhat flexible plastic, and that may be comparable to cartridge plastic.

While that is true, the mouth of the converter would be effectively lined by the tightly fitting nipple of the feed, or the hollow post in the collector or section, when the converter is attached in a manner such that the nib and feed can draw ink from it, so the actual surface area of the material used for the mouth that is in contact with liquid ink would be minimal.

 

There is also whatever material is used for the piston itself.

The plug end of the piston is usually rubber, no? Airtightness of the plug would be more of a consideration, in my opinion, but then if the plug didn't seal the cavity of the converter perfectly, then the converter wouldn't work properly in drawing ink up from the bottle.

[bemon]

I don't write all that much these days and each of my EDC pens start up just fine after a period of up to 3 days since last use:

 

Lamy 2000

Pilot Vanishing Point

GVFC Classic

 

I also used to use a Pelikan M600 which was an equally reliable writer. Though under built for the price. It got axed.

[Honeybadgers]

Does the concept of a "half life" apply when it comes to evaporation of a fixed amount of liquid? I would assume that the rate of evaporation does not depend on the total volume of liquid, only on the surface area exposed to air (all other factors being equal of course). So if a pen loses half it's ink in three months, in another three months it will lose the other half and be completely empty, right?

 

I mean, I guess the increasing concentration of ink and increase of volume of air in the pen as ink evaporates might be factors that could vary the rate of evaporation as the volume of ink drops, but I don't know how significant they would really be.

 

Yes and no. Every substance on earth has what's called a "vapor pressure", a rate at which a substance pretty much just evaporates at a given pressure. it's easily calculated, but doesn't scale lograthimically like a half life (which essentially means a substance is never "completely" gone) But the vapor pressure depends on a TON of factors, including volume of the container (a pen filled with an alcohol, which quickly evaporates, will stay liquid for a hell of a lot longer than just setting a plate of it in a room, because there is only so much alcohol that could evaporate into the air before it reaches equilibrium and just as much alcohol is condensing as is evaporating)

 

But in truth, a pen's evaporation depends on the seal with the cap and the size of the inner cap. The smaller the inner cap, the less liquid can evaporate inside it.

 

And y'all trying to compare what plastics will leech liquid are just talking nonsense. No resin used in pens is going to have a structure large enough to permit H2O molecules through it. MAYBE the H+ ions that are naturally breaking away from water, but we're picking the nittiest of nitpicks here and it's effectively moot.

 

The seal of the cap (and MAYBE the seal of the piston plunger on a converter, some chinese ones are cheap little single seal things that probably don't do a great job) and size of the inner cap is where this conversation is truly based around.

Edited August 16, 2019 by Honeybadgers

[Honeybadgers]

The plug end of the piston is usually rubber, no? Airtightness of the plug would be more of a consideration, in my opinion, but then if the plug didn't seal the cavity of the converter perfectly, then the converter wouldn't work properly in drawing ink up from the bottle.

 

Yes and no. They're usually a very firm type of rubber that, if not properly lubricated, might actually be a TINY bit of a leak. Not really in a meaningful way (so you're not technically wrong) but some converters, namely cheap chinese ones, only have a single seal and don't do the BEST job at drawing ink, so those could be a point source for evaporation.

[Honeybadgers]

I have a 20+ year old space pen that was a souvenir gift from when I was little. It was really special back then. SPACE!

 

I actually have a desk pen set that I found at a yard sale. Unfortunately it's a mis-matched set. The sac inside is also fossilized and crumbled. Your comments about the plasir and desk pen, combined lead me to the platinum carbon desk pen. Down the rabbit hole was a FPN review comment that said it was sitting forgotten in their desk for 2 years, and wrote right away.

 

Yes, the cap seal is very important. But i'm also concerned about water just evaporating directly through the permeable plastic. My noodler pens are air tight, but dry up anyways. That's why I thought maybe metal would help suppress that.

 

No, the noodlers pens lose their ink through the seal of the cap. It's not super precisely machined and only the konrad has an inner cap, but all of them have a clip-lid that extends into the cap itself. It's just not the most precisely machined pen, and the threads themselves are your weak point. If you grease the threads on a noodlers pen (which isn't a good idea because then you'd get greasy fingers, but it's just a test) you'll see that bioplastic doesn't seep.

Edited August 16, 2019 by Honeybadgers

[Arkanabar]

Hmph. No wonder I could never mitigate the amazing speed with which my Konrad dried out.

[Honeybadgers]

Hmph. No wonder I could never mitigate the amazing speed with which my Konrad dried out.

 

The ebonite and acrylic models are just made better. They will do a better job at resisting dryout, but they do cost more.

 

I love the konrad and ahab, but consider them a "fill them only when you need them" kind of pen.

[DrDebG]

O.K., I'm sold.

 

I had an old (aka 2008) Pilot Varsity sitting in my pen box. I haven't used it since graduate school (2010). I just fished it out of my box and it started right up with not leaks, blurps, anything. What a great little pen! It seems a little light to me - but it writes really well.

 

If the ink hasn't dried up at least a little in 9-10 years, I think it is fair to say that the Pilot Varsity may be the answer to your problem.

[minddance]

OP: pls provide a time frame in your topic? 3days, 1 week, 2weeks, 1 month, 2 months, half a yr?

 

ALL pens dry out eventually, it is just a matter of time.

[jchch1950]

Platinum Procyon with Platinum cartridge, was ready to write after 3 months.

[Karmachanic]

I have a Kaigelu 316 with Bock nib/housing that is remarkably dry-out resistant. It'll easily write after a month of non-use.

Edited August 16, 2019 by Karmachanic