Possible To Seal Cracks In A (Probably Rare) Plastic Converter?

[Paul-in-SF]

Today I received a really pretty pen, an Italian Estense clone of a Parker 51, in a beautiful ivory marble finish. When I unscrewed the section off the barrel I found that the filling system is a converter. The converter screws on and has a piston operation. There is an ink window next to the section.

 

However, when I went to test if it would draw water, it would not draw any, and I looked closer to see three longitudinal cracks along the sides of the converter (which is made of plastic). I am assuming that these would allow air in and thus make a vacuum, and drawing up liquid with the piston, impossible.

 

This pen was sold to me as fully functional so I can probably return it, but I'm afraid I won't find another I like so much. I am also presuming that a screw-in converter for a pen this old (from the 50's?) would be very hard to find (please correct me if I'm wrong). So I'm wondering if there isn't some substance I can safely apply to the outside of the converter that would seal those cracks, so the converter could continue to be used?

 

Here's a pretty picture, and a not-so-pretty picture of the converter with one of the cracks showing:

[txomsy]

I would try with shellac. But that's only a wild guess. No guarantees. Do not take my word for it.

[eckiethump]

Cap'n Trolley's Creep'n Crack glue, could possibly work ?

[Ron Z]

Not only do the cracks prevent ink from being drawn in, but if you managed to get ink into the converter, it would run right out again. I would try different converters to see if they fit. They don't have to be threaded.

 

I suppose that you could coat the outside of the converter with shellac and let it dry well. You might get lucky, and have it work. CT isn't likely to wick into a crack that tight, and if you used the vacuum of the piston moving down to pull it into the crack, you'd end up with CT inside the converter, and behind the seal. Epoxy or something like it might make the OD too big to fit in the barrel - I can't say for sure not knowing what the clearance is between converter and barrel.

[SoulSamurai]

Is the converter removable? It kind of looks to me like it's permanently attached to the section?

[Paul-in-SF]

Is the converter removable? It kind of looks to me like it's permanently attached to the section?

Maybe it's not removable. Those threads at the bottom that I thought might be for the converter are actually where the barrel attaches to the section. Under 30x magnification I can't tell for sure but it doesn't look like there is any division between the converter and the section. So it looks like replacing it is not a viable path.

 

Ron Z, thanks, and sorry, I don't know what CT refers to. I thought about regular old plastic model cement, doesn't that dissolve the plastic a tiny bit to make the join? That might help fill in the cracks. As for epoxy, there isn't much clearance but I thought I would be able to apply a very thin coat and make sure it's smooth while it's still wet. I would experiment with it before trying it on the pen.

[Ron Z]

CT = Captain Tolleys

[SoulSamurai]

Maybe it's not removable. Those threads at the bottom that I thought might be for the converter are actually where the barrel attaches to the section. Under 30x magnification I can't tell for sure but it doesn't look like there is any division between the converter and the section. So it looks like replacing it is not a viable path.

 

 

I was afraid of that. So it's an internal piston, not an actual converter. That's unfortunate. Hmm, I wonder if it's worth cutting it off and just using the pen as an eyedropper if you can't find a way to fix it? The body looks like a single piece so a little silicon grease on the threads (and maybe an o-ring if it will fit) will probably be all you need.

[praxim]

I would try CTCCC before I set about carving up the pen . The major risk(assuming it suits the material) is that the cracks are so open that it leaks through. You do not wish to glue the piston in place. Apply sparingly, using a point such as a toothpick to draw a fine line along the crack and to fold excess over from the side. Be patient, ready for multiple applications to make up what is missed. Give each cycle ample time to dry then examine with a good loupe for gaps or still open cracks. Keep an eye out for any leakage of CTCCC inside, which would mean either a wide crack or far too much is being applied. Taking a day or few to work through the process is good, especially with multiple cracks.

[fabri00]

It is not really a converter, but a syringae filling system.

It was widely used in the cheap Italian pen production of the 50's/60's.

Probably the filling system was produced from somebody and sold to several pen producers.

I think you can try to buy a cheap Italian pen with hooded nib from that period for few dollars, and see if you can use the filling system as spare part for your pen.

[Ron Z]

Does the back end of the unit screw off with a little heat?

[FarmBoy]

Bring it to Peters on Sunday.

[Paul-in-SF]

Does the back end of the unit screw off with a little heat?

The metal cap that holds the piston rod unscrews quite easily. Maybe too easily, it could probably use some silicone grease on those threads.

[Ron Z]

If it unscrews, you can take the piston out and seal the cracks without risk of getting the piston stuck.

 

Silicone grease will just make the cap come unscrew even more easily.

[Paul-in-SF]

I'm doing another test to see if the cracks are really the problem. I took off the metal end cap and took out the piston, immersed the ink container in water so that it would fill, and then put the piston and end cap back on, still underwater. Then I suspended the whole thing by a string over a paper towel to see if any water leaks out. It's only been about 10 minutes, but no leaks so far.

 

Is this a fair test to see whether the cracks are letting air in?

 

If the problem is not the cracks, could it just be that the piston is no longer holding a vacuum?

 

Finally, if the latter is the case, could I remove the metal cap and piston and fill the ink container with a syringe, then put the cap and piston back on, to make the pen at least usable without surgery?

 

(I should say that I don't know how to repair such a piston, although I would be willing to take instruction.)

Edited September 19, 2019 by Paul-in-SF

[Paul-in-SF]

The test above seemed to work: no water leaked out after 24 hours, so I tried to manually load ink and screw the back on to keep the vacuum, and so far that is working. In addition, the seller is going to try to find me another piston plug.

 

I may fix the cracks anyway, just for peace of mind.

 

Thanks for the advice, and for introducing me to Captain Tolley's.