The Blue Fingers Blog

Every so often a thread pops up on FPN, or I receive an email from a client saying that their Parker 51 doesn’t seem to be pulling in any ink.   “I fill it, and it seems to be OK, but I only get two or three drops out of the pen.”   Now there are occasions where something really is wrong with the pen, maybe the breather tube is damaged or missing,  but often there is not.  The pen is filling just fine, it writes fine, but their understanding of how a 51 works is, well, lacking.

The Parker 51 is one of the best pens ever made.  Steady, tough, reliable, it’s rare for one to flood unless it’s filled wrong.  It’s designed to take in a maximum amount of ink, which can take several strokes of the filler.

To be able to do this and not push the ink back out on each stroke the 51, like the Vacumatic, uses a breather tube.  With each stroke of the filler pump, or squeeze of the pressure bar, air is pushed out the breather tube which is larger in diameter than the slit in the feed.  When the filler is released, ink is drawn up the breather tube, and it flows over the top into the barrel.  Each time the filler is pressed or squeezed, more air is pushed out the breather tube but the path back out for the ink is restricted.  The process is repeated until the level of the ink reaches the top of the tube.  No more ink can be drawn into the pen because it’s pushed back out of the breather tube with each pump.

Add to the filling process the collector in a 51.  Under the hood is a collector that has what seems like a gazillion little fins.  These fins catch any extra ink that comes down the feed, keeping the pen from flooding as you write, or the ink expands in the barrel from either body heat or changes in air pressure.  It’s all designed to keep the ink in the pen unless it comes down the feed to the tip of the nib as it’s supposed to – and it works very well thank you!

You can see why measuring how much ink comes back out of a pen after it’s filled can lead to the impression that the pen is not working right.   You don’t get much back out, and you’re not supposed to.  Parker recognized this, and gave dealers a way to demonstrate that the pen was indeed filling as it should.  This illustration appears in the 1946  Parker service manual.  It’s described as a tube to “test the capacity of  Parker 51 pens.

A repairman or dealer would fill the tube to the top line with water, then fill the pen cycling the pump 10 times, pulling the pen out of the tube on the 10th stroke.  If the water or ink had dropped down to the level of the second line, the pen was working properly.  The manual also suggests that it’s a good way to demonstrate how to properly fill the pen.

When I read the manual, I realized that I need a similar way to test 51s, so I made my own testing tube.   As a matter of fact, I made a couple of them so that I could always find one.   It’s proven to be very handy in testing a 51 both before it goes out, and if one comes in for a warranty repair.

You can make one yourself.  Any tube that’s about the same diameter will work.  My 51 tester is made from a paint ball tube.  The tube is about 0.700″ in diameter, and the marks about 0.300 inches apart.  I fill to the top line, and if the the level of the liquid drops to or close to the lower line, the pen is working as it should.   The volume is  about 1.6 – 2 CC if  liquid.  The Vacumatic and aerometric 51 pens hold about the same amount of ink.

Part of the fun of repairing pens is trying to figure out how the pen was made.  In some cases, to repair the pen you first have to dig to find out how the pen was made.  In other cases you have to sit down the the broken part and your measuring tools and work out how the pen was made.

Case one is an Italian pen made around 1939.  It’s a beautiful celluloid Aurea, made I am told, buy Columbus pen.  Many of the parts were direct copies of Parker parts – the section button, etc.  It had a Parker nib, obviously incorrect since the original would have been steel.   The nib that’s now in the pen was a damaged Parker Duofold nib.  I gold soldered the crack, but some of the imprint was lost.  I removed the imprint, polished the nib, then masked it and frosted the surface.  I like the results.  In person, it’s stunning.

The pen had one significant problem – the inner cap was damaged beyond repair and had to be replaced.  There is about a zero chance of finding another cap from which to harvest the inner cap.  I was able to solvent weld the pieces of the cap together enough to take some measurements, which allowed me to make another cap.

This is the original inner cap:

You can see that it’s in pretty bad shape.  Important factors:  First, the outside.  The cap has two different outside diameters – the threaded area has to be larger.  Second, the pin at the end.  This pen fits into a hole in the clip, and holds the clip in place.  Third the threads on the cap are left hand.;  Forth, the inside diameter has to be big enough (length and diameter) for a large nib to clear.

The reason for the left hand threads is simple.  When you tighten the cap on the pen,  the section tightens firmly against the edge of the section.  When you unscrew the pen, it pulls against the inner cap until it releases.  If the inner cap had a standard right hand thread,  it would tend to loosen and come out as the pen is removed.  With a left hand thread, it instead tightens, so remains snugly in place.

Measuring diameters, lengths, thread pitch, reasoning out why certain elements are the way that they are.

Here’s a picture of the finished inner cap.  Not pretty, but it’s stuck inside where it can’t be seen, so a polished finish wouldn’t be worth the investment in time.  I used acrylic because hard rubber is a bit too brittle, and I had the acrylic on hand.  If I were to do it again, I would use Delryn, which is tougher and easier to machine.

The last interesting bit was the left hand thread.   The threads are cut left to right instead of the usual right to left.   Because the section tightens against the inner cap edge, that edge has to be unbroken.  If there is a break of any kind you end up with an air leak, and the nib will dry out.  Therefore you have to pull the bit back before it reaches the open end so that the thread does not cut across the edge of the inner cap.  But it can be done.

How long did it take?   A couple of hours perhaps.   But worth the investment in time.

The pen is not for sale.

I’m a fan of books about WW II aircraft, and all that stuff.   Given the chance, I’ll spend hours reading the books and looking at pictures.  I love air shows, especially when I have a chance to get into one of the airplanes.   A tour through a B17 was an eye opener.  One real treat though was when I got into a B29.  Really.  The (then) Confederate Air Force B29 FIFI was in Syracuse for a few days.  A kid who was working for me doing lawn work at the radio station knew a guy who was a pilot for Eastern Airlines (this tells you how long ago it was), who was one of the pilots that flew the plane. We were in.  While I didn’t get a chance to go into the back part of the aircraft, I did get onto the flight deck, look down the connecting tunnel, and watched while they worked on one of the engines.  Seeing the thing take off on a test flight was cool.  I came that close to getting to fly in it out to Michigan.  The only thing that stopped me was that I couldn’t figure out how to get back.  Bummer.

In case you don’t believe me, here’s a picture of a much younger and thinner me (with hair no less) on the flight deck.

But I digress…

What caught my eye as I was reading through a book was a comment that once in a while an aircraft would come off of the line that just about flew itself.  These things were made with the same parts, to the same specifications by the same crews, but once in a while one came out that was just right.

I think that the same thing happens with pens.  Manufacturers have the same parts, same people, and most of the nibs are acceptable and write to most people’s expectations.  But then you get one that’s just right.

I dare say that few folks ever experience a really good nib.  Most experience nibs that are good, or pretty good.   The job of a “nib meister” or skilled repairman is to produce pens that write better than the average nib, to consistently produce pens that “fly themselves.”

It is my contention that this skill is not learned over night.  It takes years to develop a true understanding of what is going on, and what it will take to make a particular nib into a smooth writer.  It’s nearly impossible to describe, so don’t be surprised if I hedge if you ask me,    On several occasions I have gone back to visit a nib that I worked on several years before, and have been surprised that I was satisfied with the work at the time.   😛    This is one area where experience really does count.

It’s unlikely that I will use the same techniques today that I used even a year ago.  Repair/nib guys are constantly growing and evolving.  If we’re not, we’re dead.  If I were to suggest just one key to learning how to do good nib work it is to observe…. the shape of the nib, the feel of the nib, and what subtle thing you did that made the difference and how you got there.

I think that I do pretty darn good nib work.  But I know that I’ve done really good work when a client writes and says “Ron, that pen you repaired has become a favorite of mine.  I just can’t put it down.”

There’s a lot of discussion about shellac.  For such a simple product, it’s surprising how much “press” it gets in the repair forums.

The short description is that shellac is made from crushed bug stuff, mixed with denatured alcohol to make a finish for furniture.  It’s been around a long time, and it’s been used in fountain pens from the early days.  You find it all over the place under different names, like “confectioners glaze”.  Yup, it’s used as a coating on candy. (if you don’t believe me, look it up!)

Pen people use it for all kinds of things like attaching sacs (sold as “sac cement”), securing sections and other things that you don’t want to move, stuff like that.  It’s used because it’s reversible.  Heat will soften it at around 103F, it’s not bothered by water (and therefore ink, which is why it’s used to attach sacs) and it can be removed easily with denatured alcohol… and it’s cheap.  A half pint can bought at a hardware or paint store will cost something like $4-$5.

Now the fun stuff.  Some people insist that for pen repair, you have to mix your own shellac, a 2 lb cut being preferable.  Then some say that you have to use a certain grade or type of dried shellac is necessary. There was a time when I bought the fancy stuff at $10 for a little bottle, and $15 for a larger one.  I can attest to the fact that it does stick well.  It certainly worked to shellac the table cloth to the table at a pen show a few years ago.  (ask me when you see me about that story)

But I abandoned the fancy stuff a few years ago.  The truth is that I have never really found that much of a difference between the fancy stuff that you mix yourself and the basic Zinsser shellac from a can.   The cheap stuff works, sacs stick.   I do use both orange and blond shellac, the later for demonstrator 51 hoods so that the shellac doesn’t show up, and mix them on occasion.  But I simply couldn’t justify the extra expense for the fancy “sac cement.”

But the real clincher for me was when I paid a visit to the Sheaffer Service Center in Ft. Madison with Richard Binder back in 2008.  There on the floor, tucked behind the fountain pen repair station was…  a gallon can of your basic hardware store variety Zinsser orange shellac.  I figured that they had done a few more pen repairs than I have over the years, and if they thought it was the stuff to use, I needn’t argue.

It happened again today.  I was working on a Mustard 51 that had a crack in the barrel, at the filler end (where else?), getting ready to do the first stage of blending the repair.  I was installing the filler so that I could check the blind cap/barrel alignment and looked inside with a flashlight to make sure that the seat was smooth because the repair went across the threads and seat inside the barrel.

I won’t go into all of the details of the repair in this post – it’s enough to say that the pen had been repaired in the not too distant past and the sac was still still pliable, though twisted into a knot.

But whomever had done that repair had not done it right.  There in the barrel, all of the way around was about an inch of dead diaphragm stuck to the barrel wall.  The cleaning that I had done to remove it from the crack had not softened it one bit.  It was stuck.

I see this quite often when a pen has been “repaired” by an amateur.  Whether a sac pen or a vacumatic filled pen, it’s not uncommon to see the remains of the previous sac still stuck to the barrel wall, pressure bar or diaphragm.  So why is that a such a bad thing?

For a sac pen there are a couple of problems.   If stuck to the barrel wall, and/or the pressure bar, the old sac will reduce the inside diameter of the pen.  The typical amateur will then grab a smaller sac, using in some cases a #16 where a 18 or 19 would be appropriate.  This reduces the ink capacity significantly, and the sac has a tendency to slip off of the section because the sac has to be stretched too much.  If it’s stuck to the section, the extra layer may make the section too big to fit into the barrel without force, and it keeps you from getting a good seal on the section.

In a Vacumatic filled pen remains of the old sac on the barrel wall can cause the diaphragm to bind as you press the plunger down to fill the pen.  If the old diaphragm isn’t cleaned off of the seat in the barrel, you’ll have an extra layer (as if you had two diaphragms stacked one on top of the other).  This will keep the filler from screwing into the barrel as far as it should.  The pen can leak, and the blind cap may not screw down as far as it should.  The typical amateur then tries to compensate by tightening the filler in even harder, which can cause barrel bulge or crack the barrel.  I’ve seen it all, and it’s not pretty.

I know that it takes a little more work to get it ALL out, but it’s worth the effort.

I’ve been impressed with the infinite number of creative ways to fill a pen.  There were of course serious motivations to avoid someone’s patent while coming as close as possible to copying another manufacturer’s ideas.  Tom Zoss says that people followed the latest developments in pen technology just as much as we do with  our smart phones today.  Lawsuits abounded because big money was invested in each new development, and the manufacturers fiercely protected their “intellectual property.”

Once in a while you come across an odd duck that came out of someone’s evasive tactics.    This past week I had an Osmia 94 cross the bench.  I haven’t been able to find any documentation on the pens (yeh, repair guys read other repair guys books and web sites) but careful examination gives you some clues to how the pen was put together and how it fills.

Exhibit 1:

If some of the parts look familiar, may I suggest looking at a Parker Vacumatic pump?  Rod down the middle, cone that slides over a rod, blind cap nut/nipple that fits over the cone, and a pin that goes through the back side of the cone to keep it in place on the rod.  No evidence of a spring inside though,  and the design in general precludes a spring up the middle of the rod as with a Vacumatic.   The spring fits into the cup at the end of the rod,  and the rod is held in the blind cap by the threaded brass nut.  Even the angle of the taper on the cone matches that found on a Vacumatic pump.  Inside the barrel, there should be a ring for the cone and diaphragm to seat against.

Like a Vacumatic, the 94 has a breather tube sticking out of the end of the feed, and the pen fills with successive strokes of the filler, the section screws in, and is sealed with a rosin based thread sealant.

So, how did it go together?  Exhibit 2:

This view shows you the diaphragm in place – note the notch for the end of the diaphragm and the pellet to go through.  The pin is in place, and rides down a slit on the other side of the rod.  The only thing not attached yet is the blind cap.  The diaphragm gets talc on the outside, and is folded back over the cone as with a Vacumatic.  A spanner is used to screw the brass nut into the blind cap, and the blind cap nipple into the barrel.

Without a spring on the pump the action is not quite as elegant because the filler doesn’t bounce back on it’s own.  You unscrew the blind cap, then using it as a knob you pump the filler up and down to fill the pen.  Like a Vacumatic, it takes several strokes.  When done, screw the blind cap back on, and wipe the ink off the nib.

It works, but I still think of it as an odd duck.