Pen Repair Don'ts

[earlier versions published in the previous century in the Pennant and the Compuserve pen forum library]

The doctor's oath begins, "first, do no harm." This guiding principle is no less applicable to the repair of old pens, yet nearly everything written to date on pen repair tells the reader what to do but not what to avoid doing. So, to give others the benefit of my misadventures, I assembled a list of what not to do. That original list has now been revised many times, and there will be more revisions to come. Any contributions are welcome we are all still learning.


A lot of pen collectors find repair work very rewarding, and there is a widespread sentiment that a pen must be in working condition to be a legitimate part of a collection. But where is the reward in a broken pen? The bare fact is, most damage to old pens comes not from neglect, but from bungled repairs.

So, step #1 should be to ask yourself if a given repair need be carried out right away, or even at all. Leaving a pen alone is unlikely to do it any harm. Most of our prize discoveries have already been sitting around for decades, and hardly are in need of immediate attention.

If the decision is to repair, the next question is whether to tackle it yourself. After reading the rest of this article, you may gain some insight into what you are up against. But keep in mind that there is no substitute for experience, and that the learning curve in pen repair is steep. Don't be afraid to have a professional work on your more difficult, delicate, or valuable pens or to set them aside until your skills are up to snuff. Practice on cheaper or already-damaged pens first.

Impatience is a major pen-wrecker. Put pen work aside if you are feeling jittery or stressed, and don't try to cut corners by using makeshift tools. Before doing anything else, make sure you understand how each pen is constructed: does the section slip into the barrel, or is it threaded? Right or left-hand thread? Is it likely to be sealed with shellac or some other compound? Are there cross-pins that have to be removed? What is the pen made of? Where are its weak spots? Study old repair manuals, but keep in mind that they were written for another era, when the pens were newer and less brittle and replacement parts were easily available. Watch pen repair videos, but keep in mind that most have been made by enthusiastic amateurs whose methods may fall short of best practice. And when you do complete a tricky repair successfully or not take down notes rather than relying strictly on memory: when it comes to the unusual, it may be quite a while before you have to do another.


Most breakage occurs in removing the section. Ideally, a threaded section would turn out effortlessly, while a slip-fit section would be snug but not tight. Reality is different. The following precautions should help you open pens while reducing risk of breakage:

Be restrained in your use of force. With proper methods, a great deal of force should not be necessary. Be especially careful in using padded pliers, which can let you squeeze sections until they crack (never use them on a section that does not have a feed inserted). Tape, by the way, is not enough padding: at least 1/16" thick rubber is what is needed, and all serrations should be ground off the jaw opening first.

Ignore old manuals that direct you to open shellac-sealed joints by striking them against a hard surface. This may have made sense for repairmen with a bucket of spare parts to hand. With age-embrittled relics for which spares are unavailable, such violence is lunacy.

Do not open joints cold. This is especially important with hard rubber barrels and absolutely essential with red hard rubber, though many older plastics have become so brittle with age that they are no less fragile. Warming the barrel mouth even slightly will reduce its brittleness dramatically, although one must be very careful not to heat it to the point that it softens and distorts. Heat is also necessary to soften shellac and other sealants about which, more below.

Be extraordinarily careful with Hundred Year pens, Coronets, any transparent pen, anything in red hard rubber or casein, and hard rubber pens with threaded sections. These pens are fragile and must be opened using special precautions. Seriously consider leaving the job to a professional.


Heat is an essential but dangerous tool; its use deserves a treatise of its own. What to include here poses a bit of a dilemma, since the line between overuse and underuse is so easy to cross. For the moment, I will emphasize what to avoid.

Some pens must be heated in order to be serviced. In self-filling pens where the ink is held in the barrel (e.g., Vacumatics, 51s, plunger-fillers, Nozacs, Ink-Vues), the section threads are typically coated with a sealant that can only be softened by warming. Dry heat is the method universally favored by professionals. A hot water bath or an ultrasonic cleaner with an integral heater will permit close control of the temperature, but many celluloids will turn cloudy and opaque if exposed to such hot water, and hard rubber is likely to fade. For this reason hot water is not recommended though other, messier, liquids can be used (oil, for example) or salt or glass beads (as used by optometrists to reshape glasses frames). In any case, temperatures must be watched carefully, since many sealants will not soften much below 160F (70C) not much below the temperature at which celluloid begins to soften. Most pens seem to need only 120-140F (50-60C), while removal of Sheaffer plunger-filler nibs usually requires the full 160F (70C).

The best overall method of applying heat is a professional heat gun with controllable output temperature (either infinitely or in steps of no more than 50F (28C) or so) and various nozzles to shape and direct the airstream. These are not cheap but the control they provide make them an essential investment. More basic heat guns with only two or three heat settings should be avoided. Note that the output temperature of even the best heat guns may fluctuate significantly when they are first turned on, so it is wise to let them run until airstream temperature stabilizes, which usually takes no more than 10-30 seconds.

Blow driers are sometimes mentioned as an alternative. The airstream, which can be focused and directed with a metal funnel, is significantly hotter than the target temperature so overheating is a danger. Some materials are very heat-sensitive, and can sustain damage even when overheated only superficially. Examples include Parker's Mandarin yellow, the plastics used for Moore Fingertips, and nearly all economy-pen plastics (cheaper plastics tended to be less carefully cured). All celluloid will soften and shrink if overheated.

Light bulbs are not an acceptable source of heat for pen work. Not only is their heat output too broadly diffuse, but exposure to such bright light at close range can darken celluloid and fade hard rubber. Note that these effects may not be immediately apparent, since discoloration can continue for some time after exposure.

Never use open flame on anything except hard rubber. Be aware that the heat of a flame can quickly erase imprints and chasing, round sharp edges, and leave permanent scorch marks. There is really no reason to use open flame in this day and age. If you doubt this, look at our article Heat Guns vs Alcohol Lamps. Even if you don't use open flame, keep an open container of water on your bench just in case, and a fire extinguisher nearby.

If you are trying to straighten a bent pen, stick to dry heat and practice on junk pens first. All internal springs must be removed beforehand, and a snug-fitting mandrel can be very helpful. Getting a bent pen straight is a lot harder than it looks.

NOTE: You will find many pens whose joints were coated with shellac before assembly. Shellac is not water-soluble, but it does soften with heat. Shellac is alcohol-soluble, but so are many plastics; hard rubber is normally unaffected by alcohols. Shellac is also soluble in ammonia, but be aware that ammonia can instantly fade hard rubber, and with prolonged exposure can also permanently discolor certain celluloids. Ammonia is also bad for gold nibs, as noted below.


Soaking is not as useful for pen disassembly as one might think. Dried ink may be the primary culprit when dealing with a stuck eyedropper section, but only secondary when dealing with a pen that uses a sac. For sac and pump-filling pens, the main obstacle will be shellac and rosin-based sealants - neither readily water-soluble. Heat is normally required to get these sealants to let go, though there is one solvent that is generally safe to use on pen plastics, and that can reduce the need for heat - naphtha. Use just a drop in the joint to be opened, and use care in heating afterwards, since naphtha is flammable.

If it is dried ink holding things together, there's no reason to soak the whole pen just to get the joint wet. Placing the pen nib-downwards into just enough water to cover the joint is a better method. Wicking water directly into the joint with a cotton swab is an alternative, though less effective when the joint is tightly closed.

Pens are designed to hold liquid, not to be immersed in it. Most lever-fillers have a mainspring and a C-shaped lever retaining spring in the barrel, and if the entire pen is immersed they may rust. Some caps also have internal clip springs; Conklins are a prime example, and are often found with caps split when those springs swell with rust. So clean caps without full immersion if at all possible (this reduces the likelihood of fading and discoloration as well). A test-tube brush and cotton swabs are useful implements. Recap the pen only after the cleaned cap has dried thoroughly, since trapped moisture can convert safely dried ink and rubber residue into more reactive forms that will promote discoloration.

Hard rubber is unpredictable. Sometimes water doesn't seem to affect it, but more often it will fade and spot. Some people claim that water-fading requires a long soak, but that is false - in many cases it is virtually instantaneous. This is especially serious with mottled and ripple hard rubbers, whose patterns may also end up standing in relief. Hot water will fade hard rubber nearly instantly, as will ammonia (many household cleansers contain ammonia beware). Fortunately, it is rarely necessary to soak hard rubber for anything except threaded eyedropper joints, and that entails immersion of only a very small part of the pen the part least exposed to light, and hence least prone to fading. This part is usually smooth, so can be polished down without harm to chasing or imprints.

Water can be unkind to plastics as well. Casein pens are rare, not least because they can be destroyed by being left in water for a relatively short period. Casein was also used for trim on hard rubber pens, typically as colored plugs or bands at the top of the cap or the bottom of the barrel. If soaked, these pieces will swell; as they dry, they will shrink again, but they may crack and no longer fit properly.

NOTE: Casein was rarely used for pens in the USA, and then only during the hard rubber era. Many English and European pens, however, were made of casein well after the advent of celluloid. Unlike their American counterparts, they are often multicolored and marbled, and difficult to distinguish from celluloid. The most commonly encountered casein pens are Conway Stewarts.

Celluloid is more water-resistant, but there are important exceptions. Metallic colors, such as the bronze found in Wahl-Eversharp green and bronze or the gold found in Conklin black and gold, can turn chalky and opaque, especially if exposed to water that is hot or which contains ammonia. Some pearlescent celluloids can be stained by prolonged immersion in inky water; again, ammonia facilitates the discoloration. If you must soak such a pen, change the water frequently.

Bleach can rapidly remove stubborn ink residue, but will also aggressively attack metals. Some advocate using it to blacken faded hard rubber, but it will often leave a coarse, porous surface that is both unsightly and unmistakable, and its effects on mottled and ripple hard rubber are even worse. Long-term effects of bleach on hard rubber are unknown. Keep bleach far away from gold and other metal pen parts. Even very dilute solutions (and bleach vapors) can cause rapid embrittlement, including spontaneous cracking.

Sometimes you will run across a pen that has been badly clogged by being filled with a solvent-based ink not meant for fountain pens. Be very careful before using alcohol to remove the ink residue; while it is safe on hard rubber, it will dissolve or soften most pen plastics (and if applied to old Pelikan barrels and other parts made of acrylic, can cause immediate crazing). Avoid proprietary cleaning solutions such as 409 and Windex they contain a witch's brew of chemicals, many of which are known to be harmful to pen plastics. Koh-I-Noor technical pen cleaning fluid comes highly recommended for removing India ink from fountain pens, particularly when used in an ultrasonic cleaner.


Do not remove the nib and feed from a section without good reason. If you do, mark their location, since they were likely heat-set. Most cleaning can be accomplished without full disassembly, by soaking, scrubbing with an old toothbrush, and flushing using a rubber bulb. Clogged feed channels can usually be cleared using a length of fine piano wire. An ultrasonic cleaner is very useful for cleaning nib assemblies, but don't use one with a Parker 61, as it can easily dislodge the inlaid arrow.

Most plastic-bodied ultrasonic cleaners are not all that powerful. Commercial and industrial units with metal bodies are often much more powerful, so if you have one, use it with care. Too long a cleaning cycle at too high power can strip plating. With any ultrasonic cleaner be especially careful when cleaning an assembly that isn't fully immersed -- for example, a barrel assembly with only the nib and section in the cleaning solution. The ultrasonic waves will propagate through the entire object, and if they converge a hot spot can develop. This isn't usually an issue with thicker barrels made of tough material, such as Parker 51 or Vacumatic barrels, but Pelikan barrels and the internal reservoir of later Sheaffer plunger-fillers are highly vulnerable to spot-overheating and blistering. Even short cleaning cycles have been known to do this, so it is safest to make sure the part being cleaned is fully immersed.

Sections are much stronger with a feed inserted. Take the feed out, and a section is easily cracked when grasped with section pliers or strong fingers. The same applies to an even greater degree to sections with interchangeable screw-in nib units - Wahl-Eversharps, Esterbrooks, and Pelikans, for example.

Wiggling a nib in or out of a section is stressful and can lead to cracking. Soak the assembly in soapy water first, heat it, then use a block and punch set to drive out the feed. Use a small punch; a big punch has too little clearance, and may end up breaking the nipple. If you cannot use a punch, as with a long-tailed feed like Parker's Lucky Curve, place a thin rubber strip over the base of the nib for more control and less stress on the tips. Warming the section will reduce brittleness and risk of breakage, and will slightly loosen the fit as the section expands. Do not use a block and punch with early eyedropper sections that are very thin at the mouth; in such cases, as with Lucky Curve feeds, wiggling or pulling is the only option, and the use of sufficient heat more critical.

Do not use a knife, razor blade, feeler gauge, or shim stock to adjust the gap of a nib's tines. Marring the interior surfaces of a nib's slit may interfere with its ability to conduct ink to the tip, and wedging the tines apart also focuses considerable stress on the area around the vent hole -- a location already susceptible to stress cracking.

Watch that tipping material! It is often very brittle and easy to break off. Don't grip the tipping material with pliers, and don't use it as a fulcrum to adjust the nib (apply bending force right behind the tips instead).

When soaking a pen, don't drop it into a glass container nib first. Plastic is safer for the tipping material; still, put the pen in gently. If you use an ultrasonic cleaner, don't let the tip of the nib touch any hard surfaces. If it does, the vibrations can sometimes be enough to break it off. Smoothing a nib on a stone is more risky than using a more yielding abrasive; use minimal pressure, and work slowly. Nibs that are deformed so that the tips cross should be handled with special care. A small scrap of thin plastic or paper between the tips will protect the tipping material from being scissored off until the nib can be straightened.

Diluted ammonia (one part household ammonia in ten parts water is often recommended) is very effective at removing dried ink, but avoid using it on gold nibs. The process may take years, but there is strong evidence that ammonia can slowly and irreversibly embrittle 14K gold by attacking the base metals of the alloy (18K gold is largely but not completely immune). Prolonged soaking - anything over a minute or two - is particularly problematic. Stronger solutions, higher temperatures, and failure to thoroughly rinse with water after ammonia exposure will all add to the risk. Use of ammonia in an ultrasonic may also accelerate the corrosion reaction.


Ink sacs and Vacumatic diaphragms will bind and stick if not lubricated. Use only dry lubricant in powder form (pure unscented talc is the traditional standby, but is not to be inhaled). For all other applications (piston seals, plunger shafts, etc) silicone grease is the lubricant of choice. Beware of "silicone" greases that are not 100% silicone: most hardware and automotive store oils and greases that contain silicone also contain petroleum distillates that will attack rubbers and plastics. Dive shops are a good source for 100% silicone greases. Note that silicone grease should not be applied to ink sacs and the interior of Vac diaphragms.


Old ink sacs can become very hard, and have to be chipped away from the nipple with a small knife or chisel-like tool. Don't begin chipping at the top of the nipple, since this is likely to break it. Begin at the base, and chip upwards instead. Wear eye protection! Heating will greatly reduce brittleness and breakage, and will soften hardened sac residue.

Don't scrape transparent parts with sharp metal tools. To clean ink-encrusted sections, transparent barrels and so on, use swabs, a test tube brush, and lots of soaking. Where there is rubber residue, a wooden dowel or disposable chopstick will take care of stubborn areas without scarring. Metal tubing can be used as a scraper, but make sure the working end is rounded off and free of nicks so that it does not scratch or gouge.

If you work in a sink, put a fine screen over the drain. If the floor of your work area is smooth, put down a piece of carpeting or corrugated cardboard. The harder the floor, the more damage when things are dropped - and the farther dropped parts can bounce and skitter.


In the old days, if a pen was taken in for repair, it was automatically buffed before being returned to its owner. Many shops still do this. This is why nearly all brassing found on old pens and pencils comes from the polishing wheel, not ordinary wear and tear. The plating is invariably missing not where a pen is normally held or handled, but in those spots that stick out into the path of the wheel: the rim of the cap top, the top of the clip ball, the middle of the lever.

Polishing a pen by hand gives better results, but takes a lot more time (which should give you some idea of how potent a material-remover the buffing wheel is much more potent than is desirable for plated metal). If you must buff, use tape to mask off the imprints and trim first. There is NO justification for putting an all-metal pen or pen cap on a buffer. Aside from causing brassing, it will instantly reduce crisp engraving and engine-turning to a blurry shadow of what it once was. Don't use Brasso on pens. It is extremely harsh, and leaves a residue that promotes trim-damaging corrosion.

Note that correct buffing wheel speed is related to the hardness of the material being polished. Hard plastics such as Lucite acrylic are quite forgiving, but softer injection-molded plastics can catch on a too-fast wheel, tearing and burning deep scars into a pen's surface. On very soft plastics such as that used for the Parker VS it is best to avoid machine-polishing entirely. Do not buff a pen with its axis parallel to that of the buffer spindle as the risk of it catching and being thrown is high. Use only the lightest pressure.

Finally, a warning about beryllium bronze, a material used for Parker clips from the Aerometric 51s on: beryllium is an extremely poisonous element, so never attempt to solder or weld broken clips that might contain it. Buffing intact clips on a wheel may also be risky.


Copyright 1999-2023 David Nishimura. All rights reserved