Parker 51 Flow Problem, Common Causes?

[chud]

I apologize if this has been discussed at length already, though I didn't find my answers on some looking...

 

I have a Parker 51 Special with a skipping, stingy ink flow problem, and I'd like to know what the common causes of this are likely to be?

 

It's a recent eBay acquisition that all in all seems in quite good shape. It filled well when I first tried it, but I discovered that it tended to write for half a line, skip or quit briefly, then start again, repeat. I figured it may be partially clogged with dried ink (there was some on the nib and in the sac), so I disassembled it for a thorough cleaning.

 

I haven't done thins with a 51 before so I went slowly and carefully, and I managed to avoid breaking anything (as far as I know). I didn't remove the sac guard, but I removed the hood and separated the collector, nib, feed, and breather tube and and cleaned them all. Ultrasonic bath for everyone, piano wire for the breather tube, and a piece of brass foil the clean to slit in the feed and between the nib tines. Everything came out pretty clean, with no observable obstructions or residue.

 

Put it all back together, and... it's better, but not fixed. When it does decide to quit I can see an air gap between the times on the nib, so it's not (or not only) a problem at the tip, and when it writes it's still a pretty dry line. Maybe it's just a very stingy flow that could be addressed at the nib, but I'm suspicious.

 

Thoughts, suggestions?

 

Thanks!!

[Moshe ben David]

Maybe time to send to a nibmeister?

[The Write Pen]

Sometimes the aerometric shells need a little work. Sometimes I increase the nib opening a little bit with a thin round fine file and it allows more ink to the page.

 

Regards,

 

danny

[ac12]

Try a wet ink like Waterman.

That is what I use in my dry 51s.

[OcalaFlGuy]

With all due respect, you should not have to "chase inks" with a drier writing P-51. The ink isn't the problem. Fix the problem. (Unless you are using one of the Very Few dry writing inks.

 

Bruce in Ocala, Fl

[TimGirdler]

There are several possible causes.

 

1. In some "51" Specials, a "51" Vacumatic collector was used--the one with the hard rubber plug. If the plug is missing, the collector will close, essentially, and the pen will starve for ink.

 

2. The lower ink channel can be clogged. Ink, of course, is a possibility, but I've seen collectors with something like metal jammed into the channel inaccessibly.

 

3. If the wide ink channel isn't at 12:00 and the feed and the nib lined up with it, the pen can--and often does--have flow problems.

 

4. The pen might suffer from the gooey sac nipple. The most recent "51" Specials I've restored both had gooey nipples--one more severe than the other. If the nipple is way too far gone, it can collapse around the breather tube and the amount of ink flowing to the collector/feed/nib is greatly reduced.

 

5. It's entirely possible that the nib tines are too close together. A good tuning can fix this.

 

6. The feed can be too far away from the nib. Essentially, the nib can be sprung, and the pen won't write.

 

7. As Danny mentioned, it is possible the nib is too tight against the shell. Though it is possible to file the shell, in my opinion, this should be a solution of final resort.

 

There are some thoughts......

 

Blessings,

 

Tim

[viclip]

It's also a good idea to ensure that the vent hole in the barrel of an aerometric is clear. Otherwise strange behaviour can develop due to the sac not residing within a normal atmospheric pressure environment. On my P51 Special the air vent is at the top end of the barrel. (I can't remember whether some P51 aero barrels have the vent along the side of the barrel near the end, but in any event it needs to be clear)

 

This should probably be the first thing checked for whenever an aero P51 displays erratic ink flow issues.

[chud]

Thanks all - it sounds like the nib adjustment or maybe the sac nipple are the most likely problem spots. I was actually using Waterman ink to test with, though I agree that should need to matter. I made sure teh barrel vent hole was clear, and I made sure the channels in the collector were correctly aligned with the nib when I reassembled it. I didn't remember to check for the plug in the collector though - another good thought, thanks. If I need one and it's missing, what's the best way to fabricate a replacement?

 

At any rate it definitely looks like I need to take it apart again. Next time I'll test before shellacing the hood back on. :-)

[OcalaFlGuy]

I didn't remember to check for the plug in the collector though - another good thought, thanks. If I need one and it's missing, what's the best way to fabricate a replacement?

A piece of the proper diameter pencil lead broken off in the channel.

 

Bruce in Ocala, Fl

[TimGirdler]

A piece of the proper diameter pencil lead broken off in the channel.

 

Bruce in Ocala, Fl

 

Yep!

 

I use 0.7mm leads, but, most likely, they'll have to be shaved down. Use some find sandpaper and roll the lead on it, back and forth, testing it often.

 

Blessings,

 

Tim

[FarmBoy]

While I have suggested to many to use a bit of pencil graphite, why not just use hard rubber rod?

[chud]

Well, one reason might be that I have pencil leads on hand (and if I didn't they can be found everywhere), and I don't know where I would start to look for a piece of hard rubber that small... :-)

 

Thanks all! It's definitely much improved even after my first pass (it now stops about once a page instead of once a line), but I'll be taking it apart again to do some more adjustment. I think it's a little dry in general, so I'll try to adjust the nib for that, and check the other items while I have it apart.

 

I also noticed that it has a round rubber washer next to the clutch ring, at the base of the hood -- it sits where the hood meets the clutch ring when it's assembled, though not visible when everything is tightened down. I don't remember this from other 51s; is this specific to the Special, or maybe I just didn't notice before? (I haven't done a lot of these yet, though I'm starting to look for them on eBay as I get more practice with them.)

[TimGirdler]

Chud,

 

The rubber o-ring is normal in the Aero pens, including the Special after a certain year (which now escapes me). I have o-rings that I've ordered that I use to replace older o-rings. Often, I find o-rings that seem to be after-market and too big. It can--and does--deform the shell.

 

The Vac "51"s and the early Aero "51"s didn't have the o-ring. It isn't absolutely necessary--if you seal the shell with shellac. I have, perhaps, two Aeros of my own on which I have, for various reasons, removed the o-ring.

 

Blessings,

 

Tim

[viclip]

Stainless steel wire can also be used as the spacer for those P51 collectors calling for same. It's OD is .025" which is a standard size & is commonly available at hobby shops, well-stocked hardware stores etc.