Do Vintage Onotos Tend To Leak?

[ImThatGuy]

Apologies for an obviously newbie question, but I did try searching.

 

I have a 6234 and a 6235 that I love to write with. Both have a tendency to leak a little into the cap. Is that normal (i wouldn't be surprised) or should I be looking for a repair?

 

Obviously one solution is to ensure I carry them cap upwards

 

Thanks for any information

 

Nick

[barriep]

They shouldn't leak into the cap. I suggest you send one to a repairer for advice and repair if needed.

[ImThatGuy]

Thanks - that helps a lot.

[ralfstc]

W-e-l-l, it depends, in my experience. The feed on Onotos was not as well developed as later pens, so if they suffer an impact, even a relatively gentle one, then ink can come out. This is MUCH reduced on the pens with the ink cut-off, like the 6234 and 6235 (any plunger filler except the Minor and a few later ones), but still absolutely possible. If you close the ink cut-off and leave the pen horizontal without impact or movement, and it still leaks, then it MAY indicate a problem, but it may also be a result of restoration. It is not easy to get the plunger rod exactly the correct length for the ink cut-off to function perfectly, plus the components may have warped slightly over time. You could also have a very slight air leak at the back end of the pen, through the sealing corks.

 

All in all, I'd say that unless it's really bothering you, and as long as they fill nicely, it's probably better to live with it (and point up storage is always best). With pens as venerable as these old beasts, I think opening them up to fix a minor quibble could, unfortunately, lead to more significant repairs being needed.

 

Hope this is helpful,

 

Ralf

Edited April 23, 2018 by ralfstc

[praxim]

Sorry to ask the "Did you plug it in?" question but I assume you shut off the pen at or before finishing writing? I have a 6235 in use now. I normally leave all my pens on their sides with few if any problems.

 

Air leakage past a worn cork seal can easily be an issue, if the shutoff is not accurate. An easy fix which might deal with this provided the corks are not too old, is to extend the plunger (on an empty pen!), add a smear of pure silicone grease around and along the rod, then operate it a couple of times before returning the pen to normal use.

[ImThatGuy]

Thanks all for those helpful and informative replies. I'll try your various suggestions and report back

[Methersgate]

A crude test that I have developed.

 

1. Screw the blind cap to the closed position, i e close the shut off valve.

 

2. OVER A SINK (!!!), or out of doors, give the pen a good hard flick.

 

3. If ink gushes, or even dribbles out, the shut off valve is not working. DO NOT TAKE THIS ONOTO ON AN AEROPLANE!!

4. If nothing comes out, the shut off valve is working as its makers intended. Congratulations. You may now leave the pen on its side, take it on an aircraft, clutch it with a hot and sticky paw, and so on.

 

EDITED TO ADD

 

Praxim makes a really good point in the post right below this one - TWO flicks!!

Edited April 25, 2018 by Methersgate

[praxim]

Sounds a good idea, provided one is a careful sort of flicker. My thought is to flick, wait a short while, then flick again.

 

The first time could just be ink in the feed. The second time will tell whether the feed has reloaded.

[Cob]

I suppose that I have rebuilt about thirty-odd Onotos, all but two had the ink shut-off feature. I have had some trouble with these, that I suspect is caused by general wear and tear. For example it is obvious that the tapered point and conical depression in the feed must be a good mating fit to seal; perhaps after - in some cases - over 100 years, this is asking too much!

 

Further, of course to seal, the point must press fairly firmly into the feed and I have found in some cases, that quite light pressure will push the feed very slightly forward which of course means that the seal will no longer be perfect. This sort of thing is inevitable with old parts - and even the youngest examples are over sixty years old.

 

At the other end of the barrel, wear to the corks will mean not just only the possibility of leaks but also that the pen will no longer fill efficiently. The suggestion to apply silicone grease is a good one: in fact I assemble Onotos using a smear on the rod, which naturally lubricates and seals the corks.

 

Cob

Edited April 25, 2018 by Cob

[praxim]

This gives me a thought. One could cut the end off a latex sac, probably in the size 12-13 range, then shellac that over the end of an Onoto plunger, providing a little give at contact and perhaps better sealing of the shutoff. I might do that experiment with one of my pens which does not need opening to write; maybe. I think I have a spare sac of that size.

[Methersgate]

Thats a nice idea. I am going to copy it

[praxim]

Go for it.

 

Just check that the added diameter on the plunger does not obstruct ink flow around it. I have not checked that myself yet.

 

One could always make the plunger one sac size smaller, -0.4 mm diameter. Pendragons, to pick one site, offer sizes to fit 4.0, 4.7 and 5.1 mm, sizes 10, 12, 13.

Edited April 25, 2018 by praxim

[ImThatGuy]

I am happy to report that an application of silicon grease seems to have sorted the problem. Thanks all for your help

[praxim]

Good news, ITG. The implication is that you will probably need to have "cork seal replacement" somewhere on your future do list but, for the time being, enjoy .