Vintage Omas Extra Cork Replacement /disassemble

[Jackokun]

Hi,

 

I have a vintage Omas extra in grey celluloid a beauty in my opinion. It uses a cork with the piston mechanism, but the cork is no good anymore is falling apart and is leaking. Can anyone help me with some guides to a) how to disassemble the piston mechanism and how to replace the cork?

 

Much much appreciated

 

 

https://imgur.com/a/qv09R

https://i.imgur.com/ET7vm0U.jpg

https://i.imgur.com/aukO6BS.jpg

[Hardy08]

Nice Arco !

I don't know this model but :

The section usualy unscreews counterclockwise, you must use some dry heat ( carefully with a heat gun for example.

Then you should extract the nib and feed from the section using a knock block.

For the piston disassembly : If it looks like modern Omas models you should find a little pin inserted through the "piston button" at the back of the pen : if it is the case get rid of this pin pushing it with a needle. You then access to the piston rod which looks like a long screew. Then you can access to the piston with the cork.

 

For the cork, I personnaly use champagne corks : you use one of the two layers of cork which are at the end of the champagne cork, they are rather good quality (feew holes). Then I cut a hole (with a drill or a small cylindrical bur) inside of one of the cork layers to the size of the pen piston. Then, with a sharp cutter blade I cut the external part of the cork roughly to the size of the internal barrel diameter. I finally fine-tune it with sandpaper. The cork should be slightly bigger than the barel internal diameter (a bit friction fit). I usualy "cook" my freshly made cork in silicone grease to provide good lubrification and tight air seal.

 

Sorry for my bad english, hope these advices are usefull to you.

 

NB : a picture of the back end of the pen should help to determine which is the piston mechanism.

 

Jeremy.

Edited January 18, 2017 by Hardy08

[Jackokun]

Here are a couple more pictures I pulled the pin out and clear a small cork ring that was there, I would assume that there it does not screw out more, but that small grey section at the end, in that case it would be better just to pull out from the section???, can I do that??

 

http://i.imgur.com/z1cpn08.jpg

 

 

 

http://i.imgur.com/rxYDWj4.jpg

[Hardy08]

uh uh...

I think the little small grey section should unscreew.

To unscreew it you must use some heat, but be carefull as exceqsive heat could melt celluloid.

Maybe you can just push the ros that stickq out from the back of the pen and recover the piston shaft by the front end of the barrel (you must unscreew the front section from the barrel to do that)

 

Good luck !

[markiv]

Hardy is right - the thin ring should unscrew.

Also is there a transverse hole in the piston rod? It could be hidden due to wax/grease from before.

If you dont then you have a bigger issue because the transverse pin secures the piston rod to the turning knob. The other end may have snapped inside the knob. I hope thats not the case.

 

http://i.imgur.com/Oov2h1I.png

[Jackokun]

Quick update,

 

good and bad, I would say, good all the instructions were good all dead on on what I needed to do , which let me do a clean up and replace the cork without any issues. The problem let after when re-assembling the section to the barrel (which i did remove at some point) I got distracted while threading it in and went wrong , since I did not noticed when i went to apply preassure to screw in a part of the barrel broke (cue in screams of pain and frustration). I have sent the pen for repair after, and while I wont get the exact yellow celluloid as ink window, the grey arco celluloid will be spared. I'll update more when i receive the pen repaired .