60-70's 149 Help With Broken Or Stuck Piston. Blind Cap Unscrews With Rod.

[scri be]

Hello and I hope this won't be too difficult a problem!

 

I have an old 149, most probably from the 60's or 70's with plastic threads and grooved ebonite (face + shank) feed, and 14c nib (more flexi).

The piston isn't operational!

 

The upper part of the piston twists out completely with the piston screw off the pen with its cap,

the screw twists freely in the cap round and round (not out), is this normal or should it be lodged inside?

this model differs in the way that the grooves for the wrench tool for the piston are not lower on the barrel next to the gold ring as they are these days, The lower part of the piston, the plastic threaded part in the ring, is stiff in the barrel and I don't know how to remove that to start reconnecting the piston, I also don't know if this piston part is threaded internally or friction fitted into the barrel.

 

I can see the piston seal near the bottom of the window it sometimes catches on slightly when I unscrew the piston but is stiff and then jumps? so I retwist a little and it comes out without catching.

 

Is it broken or just disconnected, and would some of you identify the model era? and help me out?

thank you all

 

here are some pictures

 

https://dl.dropboxusercontent.com/u/84886075/2013-10-03%2014.20.05.jpg

https://dl.dropboxusercontent.com/u/84886075/2013-10-03%2014.15.30.jpg

https://dl.dropboxusercontent.com/u/84886075/2013-10-03%2014.12.10.jpg

https://dl.dropboxusercontent.com/u/84886075/2013-10-03%2013.24.40.jpg

https://dl.dropboxusercontent.com/u/84886075/2013-10-03%2013.28.56.jpg

https://dl.dropboxusercontent.com/u/84886075/2013-10-03%2014.13.23.jpg

https://dl.dropboxusercontent.com/u/84886075/2013-10-03%2014.14.59.jpg

 

 

 

 

 

 

 

Edited October 4, 2013 by scri be

[Dillo]

Hi,

 

That's actually the press-fit piston unit, not the screw-in type. That's why you don't see any notches there. You would want someone who is good at repairing it to repair it for you, and MB service isn't really an option since it is that old, and it's probably a much better idea to repair it properly rather than replace it with a new pen. If I'm not mistaken, Maxpens should be able to take care of it for you. There are a few people in Europe who are excellent at repairing these pens.

 

Dillon

[JLS1]

Hi,

 

That's actually the press-fit piston unit, not the screw-in type. That's why you don't see any notches there. You would want someone who is good at repairing it to repair it for you, and MB service isn't really an option since it is that old, and it's probably a much better idea to repair it properly rather than replace it with a new pen. If I'm not mistaken, Maxpens should be able to take care of it for you. There are a few people in Europe who are excellent at repairing these pens.

 

Dillon

 

+1 for the above advice. I'd also suggest Francis Goosens (AKA FPN member Fountainbel), who would also be a good choice. (Happy customer, no affiliation otherwise).

[scri be]

thank you,

do you know what is broken here or is it just loose? is the rod supposed to be locked in position and not rotate?

and would you have any ideas on how to remove this type of piston unit? before I resort to sending it out, about how costly is it to fix these issues?

Edited October 3, 2013 by scri be

[talkinghead]

thank you,

do you know what is broken here or is it just loose? is the rod supposed to be locked in position and not rotate?

and would you have any ideas on how to remove this type of piston unit? before I resort to sending it out, about how costly is it to fix these issues?

 

Don't even think about it. Even the pros' like Max, Tom W. and Francis will tell you these are difficult to remove (the friction or press fit ,mechanisms ). But they have more...MUCH MORE experience than you. If you want to keep the "vintage-ness" or your pen (which I definitely would> your is a very nice early 60's model, with all correct parts), then take the advise given here and send it off to one of theses pros. It WILL be worth it.

 

Rick

 

oh, and I think the piston screw may be broke off, and not just unscrewed from the piston rod. It looks just a tad short to me...

Edited October 4, 2013 by talkinghead

[scri be]

what makes this early 60's?

 

and I'll be breaking it no more! as I've put a halt to any creepy thoughts, thanks to you.

 

but is the screw broken ?

Edited October 4, 2013 by scri be

[talkinghead]

what makes this early 60's?

 

and I'll be breaking it no more! as I've put a halt to any creepy thoughts, thanks to you.

 

but is the screw broken ?

1) See here for dating your pen....https://www.fountainpennetwork.com/forum/index.php/topic/170282-dating-montblanc-149s/

 

Your pen is a CLASSIC!!!!

 

2) It may not be broken, it just looks a little short to me like the tip may have broken off inside the piston rod...then again the remainder of the screw looks non-distorted (usually they are twisted grotesquely when snapped off), so it may have just completely unscrewed out of the piston rod itself with no damage.

 

 

Here is a picture on a 1 piece barrel and it's components broken down (screw in piston housing but the concept for piston rod and screw is the same as yours)

 

Rick

 

edited to add picture

Edited October 4, 2013 by talkinghead

[scri be]

1) See here for dating your pen....https://www.fountainpennetwork.com/forum/index.php/topic/170282-dating-montblanc-149s/

 

Your pen is a CLASSIC!!!!

 

2) It may not be broken, it just looks a little short to me like the tip may have broken off inside the piston rod...then again the remainder of the screw looks non-distorted (usually they are twisted grotesquely when snapped off), so it may have just completely unscrewed out of the piston rod itself with no damage.

 

 

Here is a picture on a 1 piece barrel and it's components broken down (screw in piston housing but the concept for piston rod and screw is the same as yours)

 

Rick

 

 

 

Question

are all the piston screws, freely rotatable, in the blind cap? I don't understand how it would spiral the rod and fill with ink if the screw could just swirl around at its head?

and also how did this unscrew itself, is there normally a stopper on the rod?

Edited October 4, 2013 by scri be

[Dillo]

Hi,

 

The piston screws are supposed to not rotate completely freely. Usually what happens is that something that gets broken in the cap that causes it to rotate like that. Definitely get it sent off for repair. It's very likely not something you can repair yourself properly. Also, the press-fit types are more difficult to remove for even experienced restorers.

 

Dillon

Edited October 4, 2013 by Dillo

[scri be]

this is what I learned from an expert

he says;

the piston shaft - part having the female lead screw thread - is broken.

the piston shaft is equipped with 4"anti rotation" ribs on its outer diameter, which slide/mate in the piston housing;

the piston would spin around instead of moving axially.

is there any detailed explanation anywhere that would explain the piston system of these pens?

Edited October 5, 2013 by scri be

[MBFan]

The spindle looks very short, so it may have snapped off. Another theory is that the pen was once repaired and not reassembled with period-appropriate parts, so that the spindle is simply too short or it was not inserted into the piston rod correctly.

 

I hope you manage to find a solution, it's a lovely 149! Good luck.

[Dillo]

Hi,

 

Did the expert see the pen? My suspicion is that the part in the blind cap that keeps the threaded rod from spinning freely is broken, not the piston shaft.

 

The piston shaft is a cylinder with four ribs on the outside and a thread on the inside and the piston seal at the end. The four ribs keep the piston shaft from rotating in the pen and allow it to only go forwards and backwards in the pen. The only thing that rotates is the blind cap and the threaded rod that is attached to it. The threaded rod shouldn't spin freely in the blind cap though.

 

Definitely send it to someone to get it checked. It might not cost that much to repair, but we won't know until someone sees it.

 

Dillon

[scri be]

Hi,

My suspicion is that the part in the blind cap that keeps the threaded rod from spinning freely is broken, not the piston shaft.

 

The piston shaft is a cylinder with four ribs on the outside and a thread on the inside and the piston seal at the end. The four ribs keep the piston shaft from rotating in the pen and allow it to only go forwards and backwards in the pen. The only thing that rotates is the blind cap and the threaded rod that is attached to it. The threaded rod shouldn't spin freely in the blind cap though.

 

Definitely send it to someone to get it checked. It might not cost that much to repair, but we won't know until someone sees it.

 

Dillon

 

so in theory a little super glue in the blind cap that would stop the screws rotation should work?

[Dillo]

The short answer is "no." The long answer is also "no" Not in theory, and not in real life either.

 

Send it for repair. It will not be possible to reassemble the piston so that it works without removing the entire piston mechanism from the pen, and you need someone who knows how to do it to do it properly without breaking the pen.

 

The piston mechanism needs to be completely reassembled outside of the pen so that everything works properly. People who have taken apart piston mechanisms on piston-filled pens that use this system will have some idea of what I mean. The parts need to be assembled in a specific order and in a specific way so that the piston can retract and extend.

 

In any case, it's a nice pen, and it shouldn't be too much trouble finding someone who can fix it here.

 

Dillon

[talkinghead]

 

so in theory a little super glue in the blind cap that would stop the screws rotation should work?

 

Despite our suggestions....it sounds like you're really itching to DIY.....don't muck it up, or you'll be ruining, again, a very CLASSIC, vintage #149 (that appears in otherwise good shape).

 

Good Luck!!

 

Rick

[jar]

 

so in theory a little super glue in the blind cap that would stop the screws rotation should work?

 

It's your pen. If you want to ruin it and make it totally worthless, feel free to do so.

[scri be]

I was trying to understand the mechanism and had no intention of practicing my theory!

I thank Dillon for his explanation

Edited October 6, 2013 by scri be

[georges zaslavsky]

I was trying to understand the mechanism and had no intention of practicing my theory!

I thank Dillon for his explanation

send it to the mentioned restorers, you will have then a great pen to write with

[penboard.de]

Hello Joe,

 

yes, this is a 149 from the first years after switching from celluloid to resin, 1964 aprox.

check the spindle attached to the turning knob,

if this still is tightly fit, and does not turn loosely,

then the piston rod inside the barrel is rotten.

 

Lucky you, as this is a lot easier to replace.

 

anyway, this friction fit piston disassembles from the front -

unscrew nib unit,

insert a pin - as large as possible -

gently heat the barrel near the barrel end -

and knock out.

sometimes the system is knocked out easyly after heating.

sometimes, it sits too tight, so you need to drill out the mechanism to keep the barrel.

 

Best regards

Tom

[penboard.de]

here is a picture,

the center type of piston is the one ...

 

http://www.penboard.de/shop/pb/149mechs.jpg

 

 

Regards

Tom