Omas Extra Piston Filler Problem

[angio]

I picked up an Omas Extra that was described as having a "broken filler". I've pulled it apart and found that the bit that protrudes from the barrel and engages in the piston rod to stop it spinning has sheared off - looks like someone tried to release the stuck piston without soaking it...

 

Anyway, the sheared part is (or at least was part of a collar that slips into the barrel and was glued into place. This in mind I have tried to replace the entire collar with a 4mm long section of brass tube with a "v" shaped indent to engage into the piston shaft.

 

In know this will work but I have encountered two problems:

 

1, The "v" indent doesn't work very well in the square channel of the piston rod - can anyone suggest a way of making a square indent as opposed to a triangle indent without resorting to panel-beating on a very small scale?

2, Fixing the collar in place - the collar is refusing to stay in place with just friction fitting and spins - Does anyone have a suggestion for an adhesive and the best way to apply it about 4cm into the barrel without clogging threads?

[hari317]

Have you tried to epoxy a square cross section post(maybe made of some wood, so that it can be shaped easily) to the inside surface of the replacement brass tube acting as collar?

 

Will shellac help keeping the collar in place?

 

ETA: This seems a job suited to Fountainbel's talents.

Edited July 17, 2012 by hari317

[fountainbel]

Hi All,

Attached a picture of an Omas piston and the mating new anti-rotation ring I've made for it.

I don't recall for which type of pen it was, so I'm not sure if it would fit in your pen

As you can see , I've made a special broach to make the internal guiding finger.

Starting from a smaller cylindrical bore one presses the broach through the ring and enlarges the bore, leaving only the width of the guiding teeth untouched

Worked perfectly !

Francis

 

http://i62.photobucket.com/albums/h89/fountainbel/Omas003.jpg

[hari317]

Francis!

[angio]

Seriously, Francis? Is there anything you can't fix?

[hari317]

Seriously, Francis? Is there anything you can't fix?

 

The problem is that he is a creator of pens, patented filling systems etc. so fixing pens is nothing but a trivial job for his talents.

Edited July 18, 2012 by hari317

[fountainbel]

Thanks for the compliment Angio and Hari !

I'm really happy when more complex repairs come in, I enjoy technical challenges.

Unfortunalely I cant get to sleep untill I found (and sketched) the optimum repair solution.........

Francis

[falkonD]

Dear Francis, I love your solution! I have got my hands on the Omas Gentleman which has the same problem.  Would you mind sharing the inside picture of your ring, I just want to figure out the dimensions and shape of that guiding rail. Also, I wonder if I can bother you with asking to create one for me. I will happily pay for it.