Slip Cap With No Inner Cap - Remedies?

[Paul-in-SF]

I recently purchased a Mentmore Diploma from the late 40's or early 50's, and discovered that the slip cap doesn't have an inner cap. The first symptom was that there didn't seem to be any firm stopping point for the slip cap when I put it on. The second symptom was that the nib was drying out pretty fast. The final symptom was when I made sure to push the cap down on the pen to prevent drying, and managed to bend one of the tines of the nib against the inside bottom of the cap. I've looked inside (now, I didn't think of it earlier) with a penlight and I can't tell if there ever was an inner cap.

 

I presume or at least hope I can get the nib fixed (it was a snappy little medium italic). But there's no point in doing that if I can't secure the nib from drying out all the time. Should I have expected this slip cap to have some kind of inner cap? And is there a way to put some kind of replacement inner cap in? Is this (the inner cap, as well as the nib) something that an experienced repair person would be able to fix? Or is the pen just a dead loss?

 

 

[PaulS]

I'm probably being a tad thick but don't entirely follow your thoughts, and notice you don't mention the chunky clutch ring that lives between section and barrel. I've peered down a few of my later Diplomas (these are the semi-hooded versions with 'stack of coins' cap rings), and as far as I can see there isn't any form of inner cap. I could be wrong but it's possible that when the caps were machined they were reamed in such a way that there is a point somewhere down from the mouth of the cap where the clutch rings comes to a pre-determined stop, thus preventing the nib from bottoming and consequent damage of tines.

 

As with most pens that have clutch rings, I assume the purpose is to help prevent the ink from drying in the feed and to create a natural stop point so the nib doesn't carry on and hit the bottom of the cap.

Does your pen have a clutch ring?

 

According to the books, this re-designed Diploma was introduced in 1948 - they must have made a lot of them as this version turns up commonly still.

Edited May 16, 2019 by PaulS

[Paul-in-SF]

Thanks PaulS for your response. I'm glad to hear from someone who has some of these to compare my pen to.

 

There is a ring between the section and the barrel. It's not very big, maybe 2mm thick, and the stepdown from the ring to the section is not very pronounced. I suppose it would be enough if there was a ledge carefully machined into the cap to catch it and prevent what happened to me. However, repeated examination of the cap with a penlight reveals no evidence whatever of any sort of machining or ridge of any kind. The pen matches your description (semi-hooded, with stack of coins cap ring) otherwise. This pen also has a semi-transparent amber-colored round end on the barrel (the pen is dark brown).

 

I take it back. Although I can't really see it, when I stroke up and down the insides of the cap with the end of a toothpick I can tell there is a thickening at probably the right spot. But it is so worn down it is almost completely smooth, there is no ledge any more to catch the clutch ring.

 

I assume there's no way to salvage the cap so that it functions properly (please anyone correct me if I'm wrong). Perhaps my best bet is to find a junker Diploma that still has a good cap. Or to find a good Diploma with a nib I don't like, and get this nib fixed and swap it out. I'm of course open to other suggestions.

[A Smug Dill]

But there's no point in doing that if I can't secure the nib from drying out all the time. Should I have expected this slip cap to have some kind of inner cap?

Even pens with slip-caps that are fitted with inner caps can dry out; my Parker Sonnet (Gold Cascade) pens — which aren't cheap — are apt to do so. Pens with screw-caps can also dry out, with or without inner caps, in my first-hand experience. My conclusion is therefore that it's only a question of whether the particular pen is apt to dry out, not how it could be categorised by cap design and then condemned to either dry out all the time or be particularly resistant against drying out by virtue of that alone.

[PaulS]

these things come as b.f. and l.f. and I've half a dozen including a couple with the coloured ends you mention, and in common with other brands that have this novelty, they often crystalize and look unpleasant. Since the brass clutch ring isn't likely to wear, then it's more probable the answer is that your cap has worn to the point that it no longer holds the section in the correct position - maybe some clutch rings are more abrasive in the cap than others, or the pen was used more frequently than most. But whatever, your cap is probably beyond redemption.

I have another example where someone converted the pen to a ball-point - and here the cap has also worn and allows the tip of the refill to hit the bottom of the cap.

Have to say I've never tried writing with one of these so no idea how they perform, but they look a sturdy robust pen and seem to have been made in several plain colours.

Suppose you might try to find a junker and cannibalize, but at the end of the day it might be easier to put this one down to experience and simply buy another in good condition. Sorry this is a bit negative but the Diploma isn't an expensive pen and am sure you will pick up another.

[Paul-in-SF]

PaulS, now that I have a second pen, I noticed that for one (the one that actually writes) the cap doesn't slip down very far on the barrel when it is as far as it will go, while the other one slips down pretty far; I tried switching caps and got the same result. So I compared the two clutch rings, and bingo -- the good one's clutch ring is actually almost 2 mm wider in diameter than the bad one's. So maybe these were manufactured differently, or maybe the one clutch ring really did wear down with use.

 

Now I'm looking for ideas for building up the outer side of a clutch ring by 1 mm with a substance that won't wear any faster than the brass did. I thought about gold leaf with sealer and several coats of some kind of urethane or something that wouldn't be too shiny. I don't know if that would work. I'm off to the hobby store pretty soon to see what I can find.