Advantages Integrated (Piston) Filling System Over Converter/ Cartridge ?

[fountainbel]

Hi all,

In reaction on the regular discussions on the benefits of a pen with an integrated ( piston ) filling system compared to a cartridge converter version, below - based on my experiences - my ideas on the matter,

Ink/air exchange is more critical on a cartridge/convertor filler compared to a pen equipped with its integrated filler system.

This sometimes results in the fact the ink flow towards the nib gets disturbed and then again restored in the repetitive manner

Problem being the pressure equilibrating airflow must enter the convertor over the small central feed nipple which is enclosed in the convertor nipple.

This implies the air flow is restricted and air has to cumulate to a larger air bubble which gets big enough to reach the feed nipple slit.

The growing air bubble sometimes disturbs proper ink flow and when the air bubble finally gets big enough to evacuate - partly ! - trough the feed nipple groove the ink flow gets restored again.

Note this cumulated large air bubble will remain in place during a writing session , only storing the pen nib up the air bubble may escape over the nib vent hole.

On a well designed fountain pen featuring an integrated filler the air enters the barrel progressively in a linear manner.

Small air bubbles enter the barrel progressively , no cumulation of air occurs hence no risks for ink flow restriction, this results in a constant linear ink flow.

Problem is that several (expensive )modern piston fillers are actually equipped with "standard" screw in nib units, featuring a cartridge.converter nipple.

I've already adapted several modern piston fillers on which the owner claimed to get irregular intermittent ink flow.

Cutting the housing nipple off and enlarging the back hole of the nib housing to a diameter being 0,5- 1 mm smaller as the feed diameter always solved the flow problems.

The attached sketch shows the differences........

Just my 2 euro cents.....

As always your comments, suggestions and critiques are most welcome….

Best regards,

Francis

http://i62.photobucket.com/albums/h89/fountainbel/Repair%20suggestions%20to%20forum/P1010195.jpg

[dms525]

Francis,

 

Thank you for this explanation. I think it could account for some of the hesitant ink flow problems in some of my C/C pens. But, it seems to me, there are so many problems that can cause irregular ink flow, the one you describe is just one of the possibilities in the "differential diagnosis."

 

A question: Are you suggesting that storing the pen nib up mitigates the problem you described in C/C pens. I just want to be clear about that.

 

Thanks again!

 

David

[fountainbel]

Francis,

 

Thank you for this explanation. I think it could account for some of the hesitant ink flow problems in some of my C/C pens. But, it seems to me, there are so many problems that can cause irregular ink flow, the one you describe is just one of the possibilities in the "differential diagnosis."

 

Sure David , both on C/C and pens with an integrated filling systems pens there may be other issues which trigger irregular ink flow,

But In my experience this is the major problem causing irregular ink flow, a problem being inherent to C/C filled pens.

 

A question: Are you suggesting that storing the pen nib up mitigates the problem you described in C/C pens. I just want to be clear about that.

 

Storing the pen nib up the cumulated air bubble may evacuate over the nib vent hole,

However when restarting a new writing session a new gradually growing air bubble will be formed and gradually obstruct the ink slit in the feed teal . At this moment the ink flow will be reduced.

At a certain moment a small part of the enlarged air bubble will break of and migrate towards the convertor.

At this moment the ink flow will get fully restored.

And this cycle will repeat itself continuously ….

Hence irregular ink flow problems will continuously reoccur.

Francis

 

Thanks again!

 

David

[Bo Bo Olson]

Converters with little springs or little floating plastic balls work better than many with out (heavier steel balls can block the entrance to the nib.)....IMO they are too narrow. Expensive Cartridges have less problems than converters.

All cartridges are expensive....no matter how cheap they appear.

 

There are better converters available ..... just don't know which ones are better and which pens the better ones fit. Lots of people save a nickle where spending a dime would solve the problem. Buy cheap; get cheap. ...even if it is a name pen....some pen companies sell cheap converters.

 

Piston pens once one lets out the three drops of ink suggested don't have that problem of lock up of ink.

Never noticed that in the thin Reform 1745 either but some said they had. So width of the piston pen can have to do with lack of stoppage problems.

Edited October 23, 2016 by Bo Bo Olson

[pajaro]

The only piston converter pens that work well for me are Montblanc 144s. I have problems with all the other brands of pens with piston converters. I have no idea why this is.

 

The piston filler pens I have work, and they stay moist and writable for months when they have ink in them.

[miel]

Thank you for the explanation!

 

But ... to be frankly ... for me the nib is much more important, than the filling system.

And so I love my Carenes eventhough they don't have pistons ... and I love my Lamy 2000 too .. eventhough they have pistons.

 

Just my 2 cents ...

[fountainbel]

Thank you for the explanation!

 

But ... to be frankly ... for me the nib is much more important, than the filling system.

And so I love my Carenes eventhough they don't have pistons ... and I love my Lamy 2000 too .. eventhough they have pistons.

 

Just my 2 cents ...

Agreed miel ,the filling system is not important as long as a pen writes perfectly

But an excellent nib mounted on a pen on which the ink flow is not stable still makes it a problematic pen…..

Francis

[Frank66]

Thanks Francis, your idea of "... cutting the housing nipple off and enlarging the back hole of the nib housing to a diameter being 0,5- 1 mm smaller as the feed diameter..." greatly resonates with me.

What I have tried numerous times in the past, in order to increase anemic ink flow in pens with flex nib modifications is to enlarge the diameter of the housing spigot with a round carbide bur, and that seemed to help some. It had never occurred to me to try to cut off the back of the housing as much as you describe. Did you have any issues with ink leakage or ink blobs when carrying your pen around?

Thanks for sharing, your proposed housing modification is one of the most interesting technical modifications I have read in FPN in a long time, and I am definitely willing to try it myself as soon as I get the chance.

- Frank66

Edited October 24, 2016 by Frank66

[pajaro]

Thank you for the explanation!

 

But ... to be frankly ... for me the nib is much more important, than the filling system.

And so I love my Carenes eventhough they don't have pistons ... and I love my Lamy 2000 too .. eventhough they have pistons.

 

Just my 2 cents ...

 

I do not think any one part of the pen is all-important. The parts have to function together. Take the Parker Sonnet, for example. There is a very nice choice of great nibs available for Sonnet. I liked the looks of Sonnet, so I ended up buying about 25 of them with a wide range of nibs. Beautiful nibs. Pens are mediocre, because the nib and feed seem to dry out too fast, as while capped between uses sometimes. Some say it's the cap that has air leak issues, whatever. The nibs are let down by the rest of the pen. So, the nib isn't everything all the time. If you pick a great pen, like Pelikan, the nib can be a deciding point between two Pelikans, for example.

[fountainbel]

Thanks Francis, your idea of "... cutting the housing nipple off and enlarging the back hole of the nib housing to a diameter being 0,5- 1 mm smaller as the feed diameter..." greatly resonates with me.

 

What I have tried numerous times in the past, in order to increase anemic ink flow in pens with flex nib modifications is to enlarge the diameter of the housing spigot with a round carbide bur, and that seemed to help some. It had never occurred to me to try to cut off the back of the housing as much as you describe. Did you have any issues with ink leakage or ink blobs when carrying your pen around?

 

Thanks for sharing, your proposed housing modification is one of the most interesting technical modifications I have read in FPN in a long time, and I am definitely willing to try it myself as soon as I get the chance.

 

- Frank66

Hi Frank,

Thanks for your reaction.

Just made a detailed complementary sketch showing the possible ink obstruction problem on a pen with a build in filling system and equipped with a nib unit featuring a cartridge/convertor nipple.

Note the proposed solution can only be used on a pen equipped with an integrated filling system, logically not on a pen on which a converter or cartridge is used.

i fully agree the shown ink obstruction does not occur on all pens with an integrated filler system, but if your pen is suffering from a cyclic irregular ink flow this will solve the problem.

In my initial posting I suggested making the bore at the bottom of the screw in nib housing 1mm smaller as the feed diameter.

This is OK on pens on which the feed is fully cylindrical at the back, but some feeds feature a flat part at the end of the feed which engages in a flat inside the nib housing.

This is for example the case with the BOCK 250 nib units with a 6mm feed.

In this situation one should make restrict the bore diameter so one still has 0.7- 1.0 mm overlap between the flat on the feed and the bore ( as shown under solution "A")

Using such a Bock 250 nib unit i therefore limit the bore diameter to 3.5mm, and in fact this diameter can be used on all screw-in nib units .

Hope this will make my suggestion more understandable.

Francis

PS Sorry, actually unable to add the Photobucket picture will try tomorrow

http://i62.photobucket.com/albums/h89/fountainbel/Repair%20suggestions%20to%20forum/P1010196%203.jpg

[WMW]

Hello

 

In regards to the suggested pistonfiller modification proposed by Francis

 

I had ...an excellent nib mounted on a pen whose inkflow was not stable... I brought it to Francis and he performed this simple and logical modification. Now my pen writes perfectly, the inkflow is rich and unhesitating, yet there have been no sudden inkblobs and no ink leakage. As I read these posts I cannot fail to notice that the technical descriptions of what happens and why at times seem more to complicate a simple act: Cut off the nipple and enlarge the back hole of the nib housing. Simple and effective: perfect flow.

To Pajaro I would say, don't protest so much on theory. Try it first. And the subject is not actually nibs.

 

Wendy

[Noihvo]

[fountainbel]

Hi Noihvo,

Glad reading you like my sketches !

Please copy them and use them as you want, there is no copyright on these !

Regards,

Francis

[Frank66]

 

Hi Frank,

Thanks for your reaction.

Just made a detailed complementary sketch showing the possible ink obstruction problem on a pen with a build in filling system and equipped with a nib unit featuring a cartridge/convertor nipple.

Note the proposed solution can only be used on a pen equipped with an integrated filling system, logically not on a pen on which a converter or cartridge is used.

i fully agree the shown ink obstruction does not occur on all pens with an integrated filler system, but if your pen is suffering from a cyclic irregular ink flow this will solve the problem.

In my initial posting I suggested making the bore at the bottom of the screw in nib housing 1mm smaller as the feed diameter.

This is OK on pens on which the feed is fully cylindrical at the back, but some feeds feature a flat part at the end of the feed which engages in a flat inside the nib housing.

This is for example the case with the BOCK 250 nib units with a 6mm feed.

In this situation one should make restrict the bore diameter so one still has 0.7- 1.0 mm overlap between the flat on the feed and the bore ( as shown under solution "A")

Using such a Bock 250 nib unit i therefore limit the bore diameter to 3.5mm, and in fact this diameter can be used on all screw-in nib units .

Hope this will make my suggestion more understandable.

Francis

PS Sorry, actually unable to add the Photobucket picture will try tomorrow

http://i62.photobucket.com/albums/h89/fountainbel/Repair%20suggestions%20to%20forum/P1010196%203.jpg

 

 

Hi again Fountainbel, and thanks so much, your drawings are superb, they helped me understand the dynamics of ink and air flow in fountain pens.

 

It is obvious to me now that this technical solution that you are proposing can only be used with pens with integrated filing systems, such as piston fillers for example. However it has been my experience that cartridge converter pens are the ones that appear more frequently to have the dry ink flow problem. Can you envision any modification of your proposed technique suited for the cartridge converter pens? If yes, I would greatly appreciate it if you could kindly post your thoughts on this matter whenever you may find the chance.

 

Thanks again,

 

-Frank66

[fountainbel]

 

Hi again Fountainbel, and thanks so much, your drawings are superb, they helped me understand the dynamics of ink and air flow in fountain pens.

 

It is obvious to me now that this technical solution that you are proposing can only be used with pens with integrated filing systems, such as piston fillers for example. However it has been my experience that cartridge converter pens are the ones that appear more frequently to have the dry ink flow problem. Can you envision any modification of your proposed technique suited for the cartridge converter pens? If yes, I would greatly appreciate it if you could kindly post your thoughts on this matter whenever you may find the chance.

 

Thanks again,

 

-Frank66

Hi Frank,

Agreed, on cartridge/convertor pens improvement possibilities are quiet limited.

In fact the best approach to overcome the intermittent flow problems would be making the nipple on the nib housing larger, but given the nipples are standardized this looks "wishful thinking".

Attached a new sketch showing a possible solution, however not tested yet.

Making a 30-45° conical internal nipple bore chamfer in the housing i expect part of the air bubble would break off sooner allowing a faster migration towards the convertor.

The picture shows a Bock 250 nib screw-in housing cut lengthwise in two .

I've applied some white paint on the cut surface so one can see the difference between the original and altered part.

What do you think?

Francis

 

http://i62.photobucket.com/albums/h89/fountainbel/Improvements%20to%20modern%20fountain%20pens/P1010198.jpg

[Frank66]

Hi Frank,

Agreed, on cartridge/convertor pens improvement possibilities are quiet limited.

In fact the best approach to overcome the intermittent flow problems would be making the nipple on the nib housing larger, but given the nipples are standardized this looks impossible.

Attached a new sketch showing a possible solution, however not tested yet.

Making a conical internal nipple bore in the housing i expect part of the air bubble would break off sooner allowing a faster migration towards the convertor.

What do you tn a Bock 250 nib screw-in housing and cut the housing lengthwise in tow pieces to show the differences.

I've applied some white paint on the cut surface so one can see the difference between the original and altered part.

What do you think?

Francis

 

http://i62.photobucket.com/albums/h89/fountainbel/Improvements%20to%20modern%20fountain%20pens/P1010198.jpg

 

Thanks Fountainbel for taking the time and effort to reply, especially with such meticulous drawing.

1. The solution you are proposing is pretty similar to what I have done in some of my pens that had extra ink flow demands, e.g flexy nib. What I did in some of these pens where enlarge the diameter of the housing spigot with a ~1.2 mm D round carbide bur, and that seemed to help some. Your proposed bevel of 30 degree may make more sense and I am willing to try it, thanks again for taking the time to make your drawing.

2. Other solution I was thinking for cartridge converter pens is, if possible, converting them into integrated filling system pens. That would necessitate completely removing the bottom round part of the housing and the spygot; also removing the corresponding part of the converter connecting it to the nipple; finally connecting the 2 parts together. The end result would be a wide mouth converter similar to the Pilot con-50 converter, which is a larger mouthed converter than the international standard. The difficult part, I guess, is connecting the modified housing and converter together in the section; this could be done with acrylic resin, shellac or friction fit, but honestly I guess this is the weakest part of the procedure. I tried it once with one of my Jinhao 450s flexy franken pen modifications, and I was not successful in preventing ink leakage. Any ideas especially welcome.

Thanks for writing back. Always respectful of people who dedicate their time and effort for improving the writing experience for all of us... Take good care,

- Frank66

Edited October 31, 2016 by Frank66

[pajaro]

Instead of doing extensive modifications to a C/C pen, why not just buy a piston filler in the first place? If money is very tight, you might buy a used pen. I have a Montblanc 144 C/C pen with a broad stub of about 1.2 mm. Flow is great. Even with Sonnet, flow for a broad stub is generous. Possibly the choice of pen is the limit on ink flow. Of course, opening up the issue of extensive modifications to an existing C/C filling pen gives you a lot to discuss and gives you something interesting and challenging to do. It does bring out pen design issues for general sharing of knowledge.

[mirosc]

Instead of doing extensive modifications to a C/C pen, why not just buy a piston filler in the first place?

A lot of pens are not available as piston fillers and some materials don't react so well to prolonged direct contact with certain inks (think celluloid and alkaline inks)

[Frank66]

Instead of doing extensive modifications to a C/C pen, why not just buy a piston filler in the first place? If money is very tight, you might buy a used pen. I have a Montblanc 144 C/C pen with a broad stub of about 1.2 mm. Flow is great. Even with Sonnet, flow for a broad stub is generous. Possibly the choice of pen is the limit on ink flow. Of course, opening up the issue of extensive modifications to an existing C/C filling pen gives you a lot to discuss and gives you something interesting and challenging to do. It does bring out pen design issues for general sharing of knowledge.

 

Thanks Pajaro, your input is always welcome. You see, for me pen tweaking is more of a hobby than anything else. And I have been experimenting with flex modification with inexpensive c/c pens and I found a lot of times feeds cannot keep up ink supply. Hence my interest in modifying the nib housing and converter.

 

I wish I had a Montblanc 144 fountain pen, I do have a similar size / era Montblanc only it is a ballpoint point, it is one of the few ballpoints present on my office desk.

 

I do have a Parker Sonnet, it was my first fountain pen, also a gift, which fell on the floor and it's nib got bent. Trying to fix this pen, this is how I learned about FPN network in the first place, around 3 years ago. My Sonnet is a wet pen, I remember I did not like this in the beginning, especially since this was a M nib, but little did I know. Now the Sonnet nib is fixed and ground to a F size, and a separate Parker F nib was also bought. The Sonnet nib is fantastic and juicy in spite of this being a c/c pen; however the pen does dry out after 2-3 weeks of not using.

 

Finally, as you said, ''... it gives you something interesting and challenging to do.'' Regards,

 

- Frank66

[fountainbel]

Instead of doing extensive modifications to a C/C pen, why not just buy a piston filler in the first place? If money is very tight, you might buy a used pen. I have a Montblanc 144 C/C pen with a broad stub of about 1.2 mm. Flow is great. Even with Sonnet, flow for a broad stub is generous. Possibly the choice of pen is the limit on ink flow. Of course, opening up the issue of extensive modifications to an existing C/C filling pen gives you a lot to discuss and gives you something interesting and challenging to do. It does bring out pen design issues for general sharing of knowledge.

Hi pajaro,

Thanks for your reaction

Note that my aim is not doing modifications on a well working C/C pen, but solving intermittent flow problems which occur on certain C/C pens.

Francis