Why Pistons, Not Syringes?

[poopypants]

 

The blind cap does little to keep a plunger from being pushed down.

 

And neither the TWISBI or Belmont are what I would consider as good designs.

You'd have to smash the blind cap with a hammer to push the syringe plunger down while it's on.

[jar]

You'd have to smash the blind cap with a hammer to push the syringe plunger down while it's on.

 

Not really. In fact you don't have to smash anything.

 

A syringe system lacks the mechanical resistance of a piston or the physical blocking of a plunger filter. Gravity works as does conservation of momentum.

 

Don't get me wrong, lots of folk like them, they are cheap to make and have been around for a long time. But for me, a syringe system ranks even lower than an eyedropper system.

[tonybelding]

 

Not really. In fact you don't have to smash anything.

 

A syringe system lacks the mechanical resistance of a piston or the physical blocking of a plunger filter. Gravity works as does conservation of momentum.

 

Well, now you've just gone into a silly scenario. The plunger is lightweight plastic, and its piston does have a "grip" on the walls of the ink reservoir. The amount of impact force required to shift it as you describe would be so extreme that the nib would most likely be ruined, if it was uncapped, or else ink would be jolted straight through the breather hole into the cap. Any fountain pen subjected to such abuse would suffer the same, and whether the plunger shifted would be the least of your worries. You just can't treat fountain pens that way.

[thefenlander]

Vendome, I am not sure if we are talking about the same thing here. I don't mean filling an eyedropper using a syringe, rather the dedicated mechanism built into the pen.

 

Jar, you note that "experience has taught us that syringe systems are prone to catastrophic failure". In your experience, what tends to fail, is it the slipping of the piston that you mention? I was looking at getting a pen with this filling system, any stories would be gratefully received.

 

Tony, I take it you have one of the Belmonts? I wish I was over the right side of the pond and had the money for one, coming from Richard Binder too I imagine they must be fantastically set up. Sorry to hear of your recent experience with the Vac 700 by the way, I am keeping a close eye on mine now.

 

Seele, thank you very much for the mention of the Chinese and Italian pens, I will keep my eyes open.

[jar]

Vendome, I am not sure if we are talking about the same thing here. I don't mean filling an eyedropper using a syringe, rather the dedicated mechanism built into the pen.

 

Jar, you note that "experience has taught us that syringe systems are prone to catastrophic failure". In your experience, what tends to fail, is it the slipping of the piston that you mention? I was looking at getting a pen with this filling system, any stories would be gratefully received.

 

Tony, I take it you have one of the Belmonts? I wish I was over the right side of the pond and had the money for one, coming from Richard Binder too I imagine they must be fantastically set up. Sorry to hear of your recent experience with the Vac 700 by the way, I am keeping a close eye on mine now.

 

Seele, thank you very much for the mention of the Chinese and Italian pens, I will keep my eyes open.

 

Yes, the catastrophic failure has been the plunger moving.

 

But again, it is simply personal preference and experience. There are folk that like syringe fillers and even eye droppers and that's great. We are lucky today to have lots of options. My favorite filling system is cartridge/converter. Some folk don't like them.

 

We each buy what we like.

[Scribblesoften]

The Ahab has the only syringe filler converter I have seen. Once, I pumped it a bit too enthusiastically and my feed shot into a bottle of ink. I've never done that with a piston filler. I think the Fountainbel bulkfiller is about the most elegant variation of the syringe fill idea to date. I like all the different filling mechanisms. They are part of what make pens fun.

[Tom Aquinas]

 

A plunger filler has far less wasted space than a syringe system.

 

In fact, personally I'd rate the normal syringe filler as the most brain dead design ever.

 

In the normal syringe filler there is noting to stop the plunger from being pushed down.

Agreed completely. It is also putting a steam engine in a rocket.

[Ted A]

The Ahab has the only syringe filler converter I have seen. Once, I pumped it a bit too enthusiastically and my feed shot into a bottle of ink. I've never done that with a piston filler. I think the Fountainbel bulkfiller is about the most elegant variation of the syringe fill idea to date. I like all the different filling mechanisms. They are part of what make pens fun.

I have that problem with the piston filling Konrad. Though it does make removing the feed and nib for cleaning a breeze. Just twist the piston all the way down

[tonybelding]

The Ahab has the only syringe filler converter I have seen. Once, I pumped it a bit too enthusiastically and my feed shot into a bottle of ink. I've never done that with a piston filler. I think the Fountainbel bulkfiller is about the most elegant variation of the syringe fill idea to date. I like all the different filling mechanisms. They are part of what make pens fun.

 

The Ahab isn't really a syringe filler. It has a breather tube and it takes a couple of strokes to fill, which makes it more of a pump-filler, or at least a hybrid. It's an odd duck.

 

I do like the Ahab's design a lot. It's a surprisingly good looking pen for the money, good sized, and the filler worked very well for me. I like everything about it except the nib and feed which were complete failure on mine.

[Sasha Royale]

If I were designing a fountain pen for manufacture, I would use the most cost-effective filling system available.

If a syringe system has better seals and durability, and cost advantage, my pen would be a syringe filler.

Next month, someone MIGHT make a piston system that is cheaper, sturdier, and better in every way. However,

I have to commit and start production this month.

 

I think a "screw" piston gives better control. A syringe filler fills in 1/5 the time. 3 seconds vs. 15 seconds.

[BrassRatt]

 

The Ahab isn't really a syringe filler. It has a breather tube and it takes a couple of strokes to fill, which makes it more of a pump-filler, or at least a hybrid. It's an odd duck.

 

The Ahab seems to fit the functional specifications of the Dunn patent, which did not specify an externally exposed "Little Red Pump Handle". There is an "air tube" and a hollow sliding pump member.

 

http://www.google.com/patents/US1359880

http://www.richardspens.com/?page=ref/fillers/fillers.htm#dunn

 

Compare this with a syringe filler:

http://www.richardspens.com/?page=ref/fillers/fillers.htm#syringe

 

Note the placement of the piston and its sliding seal.

 

 

What do all you filling system design students think?

Is the Ahab described by the Dunn patent Claim 2 or Claim 3?

 

Steve

[kauloltran]

You can design a syringe system where the blind cap has to be unscrewed from the pen's body before it can be moved, the same way the plunge fillers are designed. I don't see why this is so hard to do. A well designed syringe system should outlast a traditional screw-action type piston system by a long shot.

[RMN]

Well, I don't really know what you consider syringes, but the ones I am familiar with (like to give someone an injection with) have the end/rod sticking waaaayyy out if it is full. So a syringe filler should be at least as long as the filled container plus the rod together. This to protect that rod as that is very sensitive for small displacements.

With the screw system, especially the one by MB, you can have multiple screws, gears within gears, saving space.

 

D.ick

[Ernst Bitterman]

My main objection to syringe fillers is the number of separate items drifting around at filling time-- cap, blind cap, pen, ink bottle, wiper.

 

Twist-pistons lose one of these, and thus make for easier fillings-- cap, pen, ink bottle, wiper.

 

The same objection applies to cartridge filling (cap, barrel, section, new cartridge, old cartridge), but also button fillers (cap, blind cap, pen, ink bottle, wiper) and eyedroppers (cap, barrel, section, dropper, something to clean up the nigh-inevitable spill).

 

Gosh, now that I think about it, this fountain pen stuff is a lot of work. I'm going back to charcoal.

[UK Mike]

Way back in around 1960 I had a Platignum Varsity (Not Platinum and no relation to the Pilot Varsity) school pen which had a clear viewing window and a syringe filler which looked a little like a large converter but with a chrome operating rod at the end, connected to the piston. It worked perfectly, was very simple, never leaked and had the added bonus for a school pen that it would actually project ink some considerable distance!

 

There were no issues to prevent this filling system being just as valid and useful as any other.

 

It wasn't an expensive pen and I recall it held quite a lot of ink because the barrel was quite large diameter.

[kauloltran]

My main objection to syringe fillers is the number of separate items drifting around at filling time-- cap, blind cap, pen, ink bottle, wiper.

 

Twist-pistons lose one of these, and thus make for easier fillings-- cap, pen, ink bottle, wiper.

 

The same objection applies to cartridge filling (cap, barrel, section, new cartridge, old cartridge), but also button fillers (cap, blind cap, pen, ink bottle, wiper) and eyedroppers (cap, barrel, section, dropper, something to clean up the nigh-inevitable spill).

 

Gosh, now that I think about it, this fountain pen stuff is a lot of work. I'm going back to charcoal.

 

Syringe filling isn't the only system that needs a blind cap. What do you think about Delta's piston filler design or the Edison's bulb filling system?

[hari317]

 

The Ahab seems to fit the functional specifications of the Dunn patent, which did not specify an externally exposed "Little Red Pump Handle". There is an "air tube" and a hollow sliding pump member.

 

http://www.google.com/patents/US1359880

http://www.richardspens.com/?page=ref/fillers/fillers.htm#dunn

 

Compare this with a syringe filler:

http://www.richardspens.com/?page=ref/fillers/fillers.htm#syringe

 

Note the placement of the piston and its sliding seal.

 

 

What do all you filling system design students think?

Is the Ahab described by the Dunn patent Claim 2 or Claim 3?

 

Steve

Hi Steve, the key element on the Dunn is the sliding seal with a loose clearance, loose enough to allow ink to cross it in the down stroke of plunger. So in effect the ahab's filler is not covered by either claims in the patent. It is a plain jane syringe filler with the shaft bored out to allow the breather tube to remain attached to the feeder which is of no consequence to the filling process.

[OldGreyGuy]

I admit I like pistons having a Lamy 2000, MB149, TWSBI 580 and a Noodler's Konrad Ebonite.

 

Noting the above the Konrad while it is a piston filler, does have a blind cap.

 

Just saying.

[stuartk]

Hi Steve, the key element on the Dunn is the sliding seal with a loose clearance, loose enough to allow ink to cross it in the down stroke of plunger. So in effect the ahab's filler is not covered by either claims in the patent. It is a plain jane syringe filler with the shaft bored out to allow the breather tube to remain attached to the feeder which is of no consequence to the filling process.

 

That's true for the first stroke. For the second stroke, it functions as a Dunn filler does. Air is more easily vented through the vent tube than liquid is through the feed, so air is vented during the downstroke of the piston. Place the nib in a bottle of ink and pull the piston up and only liquid can enter.

 

The Ahab isn't exactly the same as a Dunn pen, but it isn't just a plain syringe filler either.

[FLZapped]

Parker makes one, they call it a "slide" converter. It's nice because you can operate it with one hand.

 

http://www.stylophilesonline.com/archive/jan03/06455.jpg