I've managed to remove the plexiglass sac on one of my P51s and am wondering what I need to use to properly attach it again...

(Don't ask... I was trying to remove the hood but the metal sac sheath was turning instead, so eventually to get a proper grip without damaging anything I took off the sheath and the sac too... )

I thought maybe the sac was just attached by friction/elasticity to the central section, but it leaks that way so I guess I need to use some sort of adhesive or heat treatment? The sac itself (as well as the rest of the pen) is perfectly intact.

Note that the sac is not Plexiglas^®, but likely vinyl.

--Daniel

Oops, should have said "Pli-glass"!

In any case it has a rubbery texture and is very un-glasslike, other than in its transparency.

<<bump>>

Any advice appreciated, even if qualified! I'm guessing that shellack might be an option, although as that will be difficult to get hold of I don't want to hunt it down unless I have to. Unlike the hood, it's unlikely I will ever want to remove the sac again after I attach it. The pen is an English MkII.

You are not the first to have done this, I have managed to get the sac off a "51" when I did not mean too. What I did find is that you can never get all the old sealer off the sac, the nipple is OK though. Therefore my advice is to replace the sac, Tryphon stocks them, but other good suppliers are available, and seal it back with a dab of shellac, put some more shellac on the sac guard and that should stop it coming apart again unless you heat it because you want it to come off.

Just my .02 worth

Jim

Thanks!

Just as a matter of interest, do you think the sac guards on the MkIIs and the MkIIIs less firmly attached than in the MkIs? Never had a problem with them coming off in my MkIs.

I only have one MkII so not a representative sample, but it has not happened to me, only on a MkI but I have several of those, and to be fair, the one time it did happen, I was not the first person to have a try at fixing that particular pen.

Jim

Just a couple of suggestions from the peanut gallery (I don't own a "51" at all):

- I think the aerometric ink sac on 21s and 51s is soft nylon (and Tryphon's, I *think*, is silicone)

- If the sealer is shellac, it ought to come off the sac with a Q-Tip and denatured alcohol. If it's like Parker's hood sealer (a blend of castor oil and rosin), I'd think acetone would work.

-- Brian

The material Parker used was called Pli -Glass I think, but the silicone sacs are a good replacement.

The problem I had was that if you looked at the end of the sac under a loupe, it was all out of shape and even though you could get all the muck off, getting a good seal was impossible, so in the end a new sac was the only answer.

Jim

Mine looks OK actually after I picked off a few bits at the end and washed it in hot water, and it fits on rather snugly. It forms a good enough seal as it is to be squeezed very gently (without the guard on) without leaking (any sort of vigourous squeezing causes haemorraging, however). I might try re-attaching it as it is. The most difficult thing for me will be getting hold of the shellack, I've never used it before as all my 51s have the rubber o-ring seal on the hood. I don't suppose there's anything more readily available I could use as a substitute?

Pli-Glas is just another of those great Parker tradenames ("Vacumatic", "Aerometric", "Octanium", "Lustraloy"...) -- I'm pretty sure the material is nylon.


Shellac is pretty easy to get. Online pen-repair suppliers like Tryphon have little bottles made for fountain pens, but if you'd rather buy locally, you can get a half-pint can of something like Zinsser "Bulls Eye" shellac at just about any hardware store. Apply a thin coat to the pen's nipple with something like a small artist's brush, or even a paper match, and do any cleanup with denatured alcohol. If you want to give the process a try for practice, you might be able to use rubber cement, but it won't last.

-- Brian

Thanks! I'm from the UK but living abroad at the moment and there could be translation problems at the hardware store, but I'll give it a go and if unsuccessful buy it online.



I'll probably end up using single-malt whisky as usual because it's near to hand... I know, there is a special circle of hell reserved for heresy of that ilk..

If it works, why not? Sounds like a good "patinator" (psychic, at least) for a fountain pen. Assuming you don't get too "patinated" yourself, I think the little demons will only creep out if it hurts the pen .

-- Brian

Single-malt is for drinking. Have a nice nip, WALK to the local drugstore, get some isopropanol, WALK home, have a nice nip (or two) and sit and ponder at the pen. Have another nip, buy some more pens on E-bay to keep yours company and have another nip. Then tomorrow work on the pen and you will be surprised at how easy it goes together. 51s like company and it pleases the collective if you have as many as possible. Drinking single-malt really does help in the process but the pens don't like it.

Todd

Well, I only used the Bunnahabhain, I wouldn't have wasted the Ardbeg or the Talisker...

Not sure if the shellac I got (the only one I could find) is ideal, it seemed to be marketed as a furniture polish/varnish rather than an adhesive and is just a fairly thin liquid. I hope it is concentrated enough and doesn't have any undesirebale additives.... It seems to have worked, however, and the pen is filling without leaking! Hope it lasts...

It was widely believed among collectors that the Pli-Glass sacs were made of nylon, but it has been conclusively demonstrated that they are in fact PVC (aka vinyl). Acetone really has no place in the cleaning of plastic pens, and even alcohol should be used with great discretion and care.