Miller Royal

[farmdogfan]

There is nothing about this pen that is not covered by the Dunn patent (US patent 1359880, November 1920). This patent was used by Postal to develop their bulb filler and is perhaps the most influential pen patent of all time because all other vac filler patents (including those on Parker Vacumatic) are related to mechanical detail rather than physical principle.

 

My advice is to unscrew the barrel seal, make or buy a good (well lubricated) cork seal to fit pen and plunger and try it out.

 

The reason why this design (including the Dunn pen) was not more widely used was because cork seals are insufficiently reliable and in the absence of aything better, it made more sense to use a flexible rubber diaphragm to vary the pressure rather than a fixed rod. There are a few modern pens that use a non flexible diaphragm, but they incorporate an 'O' ring seal rather than cork, and are thereby much more reliable.

Laurence

 

PS So many pen patents should never have been approved because they are re packaging of old ideas, either by making a simple idea look complicated or by using different terminology.

I can´t unscrew the barrel seal, it needs some expert treatment, so i have given up on it (at least for the time being).

[Antolin]

Just yesterday I had the same problem with a very similar pen model. I managed to unscrew everything but sadly, due to the brittle condition of the celluloid, a hairline appeared when unscrewing the section. I don't know yet whether there would be some ink leaking or not.

So, first of all, caution is a good thing. Second, I think that the threaded bushing is not glued but very tight. It was very hard to unscrew but you would only need a way to hold it firmly. I did it wrapping a taut rubber strip, after a 48 hours in a water bath with some drops of dish soap.

 

http://s22.postimg.org/5maou5mr5/w_1070904.jpg

Here are the results. Now I have to investigate how to keep the rubber sac in place, because the old crystallized one seems to be glued to the barrel wall (maybe is due to its degradation). BTW I don´t understand how it could be substituted by a cork seal.

Edited October 16, 2014 by Antolin

[farmdogfan]

Just yesterday I had the same problem with a very similar pen model. I managed to unscrew everything but sadly, due to the brittle condition of the celluloid, a hairline appeared when unscrewing the section. I don't know yet whether there would be some ink leaking or not.

 

So, first of all, caution is a good thing. Second, I think that the threaded bushing is not glued but very tight. It was very hard to unscrew but you would only need a way to hold it firmly. I did it wrapping a taut rubber strip, after a 48 hours in a water bath with some drops of dish soap.

 

http://s22.postimg.org/5maou5mr5/w_1070904.jpg

 

Here are the results. Now I have to investigate how to keep the rubber sac in place, because the old crystallized one seems to be glued to the barrel wall (maybe is due to its degradation). BTW I don´t understand how it could be substituted by a cork seal.

Yes that looks like mine.

 

You are probably right, maybe some celluloid shrinking is playing a part as well, i did use rubberstrips and all other devices known to mankind, so i did´nt have any problem getting a good grip, but this one is really tight, if i had gone further something wouldn have broken so i choose to leave the §#"¤&* thing alone, for a while at least.

 

Getting the sac to stay in place is probably not an easy task.

 

I´m looking forward to see your progress.

 

Regards Per.

[Antolin]

After years repairing old fountain pens I have found out that a long bath in water with some drops of dish soap is miraculous. Even more if iron gall inks has been used.

On the other hand, the barrel (mine at least) has two parts, the front one made of transparent celluloid and the rear part, made of a black one. I can't figure the use of it because the transparent half seems to be inside painted of black (like old 100N Pelikan sections), but this is another question. The point is that I think the transparent celluloid part is much more brittle than the rear one but being careful is a good idea.

 

http://s8.postimg.org/p263d6llx/w_IMG_3237.jpg

I'm beginning to figure out a way to fix the diaphragm. I'll show it if I succeed.

[farmdogfan]

I´m looking forward to your solution.

Good luck.

[Flounder]

Very interesting Antolin, thanks for the photos. The transparency is very attractive - does the barrel also transition from round to octagonal?

 

Laurence, I think this design differs too much from sacless fillers like the Dunn to successfully retrofit a cork seal, as the space provided to clamp the walls of the original rubber 'elastic membrane' is likely very thin. Even if it a thin enough cork/O ring were ground and fitted, the plunger's return action, originally intended to be performed by the elasticity of the membrane, would be down to the user to perform.

 

It's an interesting if crude design; it gives the diaphragm the work of a Parker Vacumatic's return spring, as well as altering the barrel volume. I'm not sure I prefer rubber being stretched rather than folded (which the patent denigrates to amusing excess) to accomplish the latter, but it all strikes me as a charming piece of filling system history, handsomely executed. The cap band in particular is hypnotic!

Edited October 16, 2014 by Flounder

[lcoldfield]

Now that it is dismantled, I can see that a fairly major modification would have to be done to fix a cork seal. It looks to me as though the original flexi diaphragm may have had a flared end so that the threaded bush would clamp it to the inside of the barrel where there is presumably a ledge? The senior Ink Vue diaphragm has a flared end - it may work. Folding down the end of a conventional sac may also work.

 

Regarding removal of the old diaphragm stuck to the inside - there is tool available from craft shops that is like a wood carving gouge for convex surfaces - it is very useful for removing debris inside barrels.

 

Good luck,

Laurence

[Antolin]

It is not as easy as I thought. I have taken a #18 sac, I cut it a bit longer than the wider rod, then I lubricated the rod with talc powder and inserted the sac. In order to make a flange-like ring to be trapped with the bushing, I rolled the rim (like a condom). But, what I never expected was that an usual rubber sac is too thick to be housed between the barrel and the rod.

The only solution I can imagine is to use a thinner sac as the ones for snorkel filling mechanisms, but I don't have any. Besides, I don't remember if there are thin sacs like these wide enough.

So, I am blocked again.

 

http://s30.postimg.org/nkojmqma9/w_IMG_compl2.jpg

[farmdogfan]

Nice try though, maybe some kind of special made sac is needed.

[Flounder]

Antolin, if it's not a hassle could you please photograph the filler end of the barrel cavity? I'd like to see the patent's "ring E" in real life.

[Antolin]

No problem, but I'll have to do it tomorrow morning to have good natural daylight.

Edited October 17, 2014 by Antolin

[Antolin]

As I promised, here are the photos you asked for.

It can be seen that inside there is a kind of a metal casing attached to the barrel. It seem metal to me but may be it is only an ink residue that glows as metal. Anyway, in the last picture I put the rod to show how narrow is the free space around it.

 

http://s29.postimg.org/9w3pr8t6v/w_IMG_3252.jpg

 

http://s29.postimg.org/9utrxtrd3/w_IMG_3254.jpg

 

http://s29.postimg.org/8igo9ojbb/w_IMG_3260.jpg

 

I forgot to say that the rod is upside down, just to show how fits the widest part of it.

Edited October 18, 2014 by Antolin

[Flounder]

Excellent photos Antolin, it's very fortunate you happened to come by this thread. Hugely helpful

 

That certainly looks a very thin space. A couple of ideas spring to mind;

 

1. Is the ring fixed in the pen?

 

2. Perhaps there's some sort of fiddly knack to fitting the sac/diaphragm in place, as there is with Parker's diaphragms.

 

I would be inclined to begin by leaving the sac uncut, and lubricated with glycerine inside and out.

 

Then slide the push rod all the way into the sac. Then insert the sac from the section end of the barrel, and start pulling the uncut ink sac up the barrel from the filler end.

 

The empty end of the sac should easily pull up through the ring, and by the time the lubricated rod end of the sac reaches the ring, pulling on the empty end, perhaps with a rotating action, might overcome the clearance issue. Then trim the excess rubber, leaving enough for the threaded boss to clamp down upon securely.

 

3. As farmdog suggests, it might have used a proprietary diaphragm. The patent does refer to a "flange on the diaphragm".

 

4. I know I have large diaphragms somewhere for you to try. I can't find them anywhere!

 

5. You can buy them from the Pendragons, as well as the narrow wall touchdown sacs.

Edited October 18, 2014 by Flounder

[Antolin]

Yes, it is fixed in the pen.

I am beginning to think that a proprietary diaphragm was used. But on the other hand, yesterday I discovered that Poul Lund is going to be at the next Madrid's Penshow, to be held next November. I'll try to contact him just in case he knows how to repair this pen or where to find this kind of diaphragm.

Edited October 19, 2014 by Antolin

[farmdogfan]

Sounds like a good idea, he would probably know.

[Antolin]

I have realized that there is another final extreme solution. That is to turn the rod thin enough to give space for a sac, using a drill as a lathe.

Edited October 20, 2014 by Antolin

[farmdogfan]

I use mine as an eyedropper, if i should i want to write with it.

[fpnnm]

I have just a suggestion: consult member fountainbel , who, along with lcoldfield (no affiliations), have reputations on this board of being adept at repairing and doing workarounds on vintage fountain pens. Both are based in Europe, I believe.

Edited October 22, 2014 by fpnnm

[lcoldfield]

Coming back to my original suggestion of dumping the rubber diaphragm and using a cork seal at the barrel end, I see from the photos that this is very possible because of the large smooth shoulder inside the barrel against which the end can be comprssed by the threaded plug. The threaded plug will have to be halved in length to allow room for the cord seal. The cork seal should be a good fit to the plunger and should be lubricated with wax and silicone grease.

The only downside in doing this is that the pen is not quite original in construction any more and the plunger will have no return spring action. The number of cycles to fill will be the same as if the plunger were covered with a rubber diaphragm.

Laurence

[farmdogfan]

I just unscrew the section and fill it with ink an then screw the section on again, and it´s ready to write, no sealant is needed (not on my pen anyway).