Alternative For End Cap / Cork Seals

[kdv]

Ls,

 

 

As an amateur repairer off fountainpens I face more and more the challenge off replacing cork seals.

One of the main problems is that quit often the end cap (the disc that prevents the cork from slipping off) is (partially)broken.

Has anybody found a solution for these problems? Should I glue the cork on the piston rod or is there a way to make a new end cap?

Greetings

 

kdv

 

[fountainbel]

The cork is on most pens axially enclosed with a nut or a screw with large collar.

Getting these loose is mostly facilitated by overnight soaking, processing the piston rod in an US leaner or applying some heat.

Glueing the cork on the piston shaft is possible, but drawback is that there is no possibility to expand the cork radially by tightening the nut or screw.

Hence one needs to make a more perfect fitting cork, which normally features a radial pretension of 0.15/0.20 mm in the barrel bore.

Making a replacement nut or screw is surely possible, but one needs a lathe do so.

Francis

[kdv]

Thanks Fountainbel,

 

So, I go for the perfect fitting cork. Some additional questions:

• Radial pretention ca. 0.15/0.20 mm in the barrel bore., means: ca. 0.15 mm wider than the barrel bore (inner barrel diameter)?
• Shellac for gluing the cork oke?
• the type off piston in question has not an “anti-rotating-groove” (or alternative like that) that prevents the sealing from rotating. The friction of the cork/seal should just be more than the friction of the rod for correct functioning (up-down movement). Therefore: should I use stearine/beeswax and silicone grease for the cork? It could get to smooth. And if so can the cork still expand a little when it is saturated with water (ink) for a right fit?

Thanks and greetings,

kdv

[fountainbel]

Hi Kdv,

Please find my replies in your text below.

Wishing you success !

francis

Thanks Fountainbel,

 

So, I go for the perfect fitting cork. Some additional questions:

• Radial pretention ca. 0.15/0.20 mm in the barrel bore., means: ca. 0.15 mm wider than the barrel bore (inner barrel diameter)? Right, !
• Shellac for gluing the cork oke?When there is no alternative, yes
• the type off piston in question has not an “anti-rotating-groove” (or alternative like that) that prevents the sealing from rotating. The friction of the cork/seal should just be more than the friction of the rod for correct functioning (up-down movement). Right, but in this case I would surely go for a radial pretension of 0.2mm Therefore: should I use stearine/beeswax.Yes, always soak the finished cork"au Bain Marie" in a beeswax/liquid paraffin solution. and silicone grease for the cork? Applying some silicone grease or pure vaseline to reduce the friction force is sometimes beneficial It could get to smooth. And if so can the cork still expand a little when it is saturated with water (ink) for a right fit? When the cork is properly soaked it will hardly expand when exposed to ink or water

Thanks and greetings,

kdv

[kdv]

Thanks again fountainbel.

 

I succeeded for 99,9 % following your instructions.

 

There were though complications: the major one:

• Pushing/screwing back the new cork into the barrel was accompanied with a lot of friction. But, when inside and the sealing at the position of the ink window there was almost no more friction, so the sealing turned just around instead of up- or downward.
• Apparently at the Hight of the window most pens are at their max diameter
• After taking out the cork and doing again an au bain marie everything works just fine!!!!
• BUT: should I have recorked from then front off he barrel instead from the back end. What is your advice: cork from the back or from the front?

Sorry for all these questions, nice day,

kdv

[fountainbel]

Well done kdv !

As for installation of the cork from the back or the front :

1-On pens were the complete filler assembly - including the cork - can be removed from the back one should logically reinstall it from the back. On most of these pens unscrewing the section from the barrel Is not possible since section & barrel are made in one piece.

2-On pens were the section can be unscrewed from the barrel one can mostly remove the piston rod from the front and reinstall it after re-corking. When the piston rod features an anti rotation keyway it may take some time to get the piston back in but with some patience you will surely succeed

Francis

Thanks again fountainbel.

 

I succeeded for 99,9 % following your instructions.

 

There were though complications: the major one:

• Pushing/screwing back the new cork into the barrel was accompanied with a lot of friction. But, when inside and the sealing at the position of the ink window there was almost no more friction, so the sealing turned just around instead of up- or downward.
• Apparently at the Hight of the window most pens are at their max diameter
• After taking out the cork and doing again an au bain marie everything works just fine!!!!
• BUT: should I have recorked from then front off he barrel instead from the back end. What is your advice: cork from the back or from the front?

Sorry for all these questions, nice day,

kdv

[fountainbel]

Well done kdv !

As for installation of the cork from the back or the front :

1-On pens were the complete filler assembly - including the cork - can be removed from the back one should logically reinstall it from the back. On most of these pens unscrewing the section from the barrel Is not possible since section & barrel are made in one piece.

2-On pens were the section can be unscrewed from the barrel one can mostly remove the piston rod from the front and reinstall it after re-corking. When the piston rod features an anti rotation keyway it may take some time to get the piston back in but with some patience you will surely succeed

Francis

Thanks again fountainbel.

 

I succeeded for 99,9 % following your instructions.

 

There were though complications: the major one:

• Pushing/screwing back the new cork into the barrel was accompanied with a lot of friction. But, when inside and the sealing at the position of the ink window there was almost no more friction, so the sealing turned just around instead of up- or downward.
• Apparently at the Hight of the window most pens are at their max diameter
• After taking out the cork and doing again an au bain marie everything works just fine!!!!
• BUT: should I have recorked from then front off he barrel instead from the back end. What is your advice: cork from the back or from the front?

Sorry for all these questions, nice day,

kdv

[siamackz]

Check out custom pen parts. He has nuts for MBs and may be able to make you for other models? http://www.custompenparts.co.uk/mont-blanc/74-locking-nut.html