National Controllor, leaking button filler

[jagarpether]

Hi.

I got this National Controllor button filler pen of an auction, but the filler leaks a little around the button.
Does anyone know how to fix this?
It is a really nice pen with a nice flexy degussa 14k nib.

22976

/Pether

[Jeph]

That is a nice looking pen. I have never seen that style of button before but if ink is coming out from the button the sac must be ruptured or loose somewhere. There should be no ink touching the button. And those ends look like hard rubber so don't soak them in water.

[jagarpether]

That would be easy to change but this pen does not have a sac. The barrel is clear so you can see the ink through it. Somewhere i read that this type of filler have some sort of piston that is connected to the button, and the feed have a breather tube so it vorks as a vac. But of course it can have a sac as a Parker 51.

[Jeph]

Ooooh, that is neat but that also sucks. Because that means that there is likely a diaphragm on the bottom of the button that will (probably) require a custom replacement. Likely some variation of the Parker vac arrangement.And I have no idea if they solvent welded the parts together or if they are just threaded. Hopefully an expert will chime in and either help you fix it or tell you a good place to send it.

Does it draw and expel water well? And using water, how much leakage do you get at the button?

Oh, and I would add that at least I think that is worth fixing without question.

[jagarpether]

I have tried to watch for threads but it's hard to see. That's why i'm asking here :)

It draws water really well, and it dosen't leak that much, but it's noticeable and especially when the button is pressed.