Plunger/Vacuum-fillers - unscrew knob for ink flow?

[FredRydr]

Today, a box of ink arrived from Goulet Pens. Enclosed is Goulet's little pamphlet giving instructions on various pen-related things, one of which came as a surprise to me. That is, to enable ink flow in vacuum-fillers (plunger-fillers in my parlance) when writing, unscrew the knob that's attached to the plunger rod. I've been under the impression that once the knob is screwed all the way home after a fill, the plunger washer and backing washer on the end of the plunger rod stand clear of the inside surface of the barrel such that they no longer seal.

All my plunger-fillers have been vintage '30s-'40s pens from Sheaffer, Wahl and Aurora. Does the plunger design in vacuum/plunger fillers manufactured today require the knob be unscrewed for ink to flow when writing?

[Farmboy]

I know not about pens made today but Sheaffer and Wahl did not require opening the back end.

Many vintage Japanese pens are mistaken as plunger filled when they are really dropper filled and the back end operates an ink shutoff that should be loosened eversoslightly for flow.

[FredRydr]

FYI:

SheafferVac.jpg

[mreeveshp]

I have the TWSBI Vac700r (EF) and with the knob screwed down I can write about a page before I have to unscrew the knob and let ink flow from the barrel to the feed. I normally just leave mine unscrewed so it's always ready.

From what I understand they were designed in theory that you could have the knob screwed down which makes the plunger seal between the barrel and feed so that when you are on a plane or changing altitudes it would keep it from leaking ink like a normal cartridge filled pen would.

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[Jon Szanto]

Yes, some of the newer pens have a shut-off valve, often in combination with a small ink chamber behind the feed but in front of the barrel. The idea is that you have a small amount of ink always at the ready, but when the piston knob is completely closed, it closes off the main ink reservoir, avoiding burps/spills/etc. If you need more ink you just unscrew a bit. If I'm not mistaken, the Aurora piston fillers have something similar.

I'm fairly certain the popular Pilot 823 is built this way, a number of Chinese and Taiwanese pens (PenBBS/TWSBI) are, as well. I recently got a Ben Walsh / Gravitas "Ultemate Vac" (shown below) that incorporates this feature (you can see the ink chamber ahead of the titanium barrel piece) and calls it out on their product page. Pen is made of Ultem and titanium and is very well made... except it doesn't suck up quite as much ink as my vintage Sheaffers.

ultemvac.jpg

[Chrissy]

I was aware that the TWSBI VAC 700 needed to have the piston knob unscrewed before it would write. It slightly put me off buying one because although I'm not a frequent flier I've never had a problem with any leaking pens on a plane so I didn't see the need to have to remember to screw a piston knob up and down.

[mreeveshp]

I was aware that the TWSBI VAC 700 needed to have the piston knob unscrewed before it would write. It slightly put me off buying one because although I'm not a frequent flier I've never had a problem with any leaking pens on a plane so I didn't see the need to have to remember to screw a piston knob up and down.

With mine I can write a decent amount before I have to open it because of the EF nib, this was my dream pen (I know there is better) I just love the iris look but it does get annoying sometimes opening and closing so I just leave mine open and haven't had a problem.

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[Motomachi10]

Opus 88 needs to unscrew the knob for ink flow after one page.

[Osiris]

I was aware that the TWSBI VAC 700 needed to have the piston knob unscrewed before it would write. It slightly put me off buying one because although I'm not a frequent flier I've never had a problem with any leaking pens on a plane so I didn't see the need to have to remember to screw a piston knob up and down.

I mean, you don't have to screw down the knob, so you don't need to let that deter you from picking up the pen if you really like it. You can just leave it cracked open and have the knob sit on the last threads of the screw thread, this will allow ink to flow freely at all times. You can also remove the front O-ring that seals the antechamber from the barrel, then the flow is always unrestricted(even when the knob is screwed down). It's not the same O-ring that makes the seal with the barrel to facilitate the vacuum filling mechanism, that's a wider O-ring that sits behind the smaller one at the end of the rod.

What I always do with my eyedroppers, vacuum fillers and bulk fillers is I leave them open as far as I can unscrew them without screwing the knob off of the thread completely. Then when I go to travel, I pull the rod out of the barrel to suck the ink out of the feed and then you can push the rod back forward and close off the antechamber.

[calamus]

What I always do with my eyedroppers... [snip] ...is I leave them open as far as I can unscrew them without screwing the knob off of the thread completely. Then when I go to travel, I pull the rod out of the barrel to suck the ink out of the feed and then you can push the rod back forward and close off the antechamber.

I'm not sure what you're referring to; I've never seen an eyedropper with either a knob or a rod. Could you please explain it to me? I think I must be missing something.

[Jon Szanto]

What I always do with my eyedroppers... [snip] ...is I leave them open as far as I can unscrew them without screwing the knob off of the thread completely. Then when I go to travel, I pull the rod out of the barrel to suck the ink out of the feed and then you can push the rod back forward and close off the antechamber.

I'm not sure what you're referring to; I've never seen an eyedropper with either a knob or a rod. Could you please explain it to me? I think I must be missing something.

I believe this first started with Japanese ED pens, decades ago (50s? 60s?). You still fill the pen by unscrewing the front and dropping in the ink. However, there is a mechanism that looks just like the plunger knob on the back end. The function of this is that the rod extend all the way into the barrel, and there is a gasket on the end. When the knob is screwed in completely, it pushes the gasket onto the opening that allows the ink to flow from the barrel to the feed, effectively closing off the barrel and ink supply. They came up with this to negate the situation of an ED pen spilling or burping ink into the cap while in transit. To open the ink channel again, all you need to do is unscrew the knob a turn or so and the ink will flow. Quite ingenious.

There are a number of current pens that use this, and as mentioned, the Opus 88 eyedropper pens incorporated this convenient shut-off valve.

[Osiris]

What Jon said. Basically, just imagine a vacuum filler but the larger of the two O-rings isn't there and the barrel is completely straight instead of widening out towards the grip section. So it has the ink shut-off, but not the vacuum filling part.

On a side note, I really wish people had made more of a point of calling what we refer to as "Japanese eyedroppers" just "eyedroppers" decades ago, though I guess they weren't as widely known back then. "Crappy cartridge/converter pen hack" would be more appropriate for the other one.

[PPPR]

The Asvine V169, a current vacuum filler, came with instructions to unscrew the end cap slightly when writing. Otherwise it dries up.

[calamus]

What I always do with my eyedroppers... [snip] ...is I leave them open as far as I can unscrew them without screwing the knob off of the thread completely. Then when I go to travel, I pull the rod out of the barrel to suck the ink out of the feed and then you can push the rod back forward and close off the antechamber.

I'm not sure what you're referring to; I've never seen an eyedropper with either a knob or a rod. Could you please explain it to me? I think I must be missing something.

I believe this first started with Japanese ED pens, decades ago (50s? 60s?). You still fill the pen by unscrewing the front and dropping in the ink. However, there is a mechanism that looks just like the plunger knob on the back end. The function of this is that the rod extend all the way into the barrel, and there is a gasket on the end. When the knob is screwed in completely, it pushes the gasket onto the opening that allows the ink to flow from the barrel to the feed, effectively closing off the barrel and ink supply. They came up with this to negate the situation of an ED pen spilling or burping ink into the cap while in transit. To open the ink channel again, all you need to do is unscrew the knob a turn or so and the ink will flow. Quite ingenious.

There are a number of current pens that use this, and as mentioned, the Opus 88 eyedropper pens incorporated this convenient shut-off valve.

Thank you for explaining it to me. The only eyedroppers I've ever had were the kind that burp.

[Robalone]

Hi. All the old Onoto plunger fillers required that the knob be unscrewed a quarter turn such that the conical bit on the end of the rod disengaged a small amount from the feed tube.
Personally, I find their plunger / vacuum fillers one of the most tedious fillers ….contrary to a lot of folk's opinion that it was/ is one of the best !!!
What I do with my Onotos is unscrew the knob til the ink starts, then shut it off again, cos there’s generally enough ink to write quite a lot with just what gets into the feed.

And they are a royal pain to fix , with their tiny little hard rubber pins and left hand threads and fragile rods …….

Sorry….bit of a whinge there 😂

[Frank Wilson]

Today, a box of ink arrived from Goulet Pens. Enclosed is Goulet's little pamphlet giving instructions on various pen-related things, one of which came as a surprise to me. That is, to enable ink flow in vacuum-fillers (plunger-fillers in my parlance) when writing, unscrew the knob that's attached to the plunger rod. I've been under the impression that once the knob is screwed all the way home after a fill geometry dash online, the plunger washer and backing washer on the end of the plunger rod stand clear of the inside surface of the barrel such that they no longer seal.

All my plunger-fillers have been vintage '30s-'40s pens from Sheaffer, Wahl and Aurora. Does the plunger design in vacuum/plunger fillers manufactured today require the knob be unscrewed for ink to flow when writing?

In the case of vintage plunger-fillers from the '30s-'40s, you are correct in your understanding that once the knob is screwed all the way home after a fill, the plunger washer and backing washer on the end of the plunger rod stand clear of the inside surface of the barrel, creating a seal to prevent ink from leaking.