18K Nib Question

[proton007]

I won't say gold nibs are 'flexier'.

 

But they feel more 'muted' to me. The scratchiness depends on the tip, but I just don't get the same 'feedback' in gold nibs as I can get in steel.

[pico]

a bit of different interpretation on terminology seems to be going in different directions.

 

Pure gold is 24k all the way through.

Solid gold can be seen as "its not plated" but can be solid 10k, 14k, 18k, 24k gold.

 

The tipping material is what you write with and is extremely hard and durable. Its grind will determine how smooth it is while riding the surface of the paper.

 

The design/shape of the nib will determine the amount of "flex"; if by "flex" the meaning is the amount that the tines separate with some pressure.

 

Gold is softer and more flexible than steel. So, another aspect of a gold nib is a shock absorbent effect depending on your writing style to make the experience smoother. But, not necessarily that the tines separate for a wider line.

 

Gold is not necessarily very flexible. I have 18k rings and you cannot just bend them with minor, or even pretty good, pressure. And, 14k is a pretty strong alloy in terms of "bendability". Its the shape of the nib that really will determine how bouncy or flexible it is.

[Bo Bo Olson]

It depends on which metals and % are in the alloy of 585 or 750 gold. That is a key to flexibility.

Depends also if the nib is forged or rolled.

Edited March 19, 2014 by Bo Bo Olson

[Sandy1]

Hi,

 

I see no practical correlation between flexibility and durability, so long as the nib isn't sprung.

 

IMHO any difference in 'durability' would be related to the cosmetic two-tone plating [OooLaLa] - not the functional aspects of the nib alloy.

 

There was some concern raised about the gold-plating on steel nibs being degraded when cleaned in an ultrasonic bath, but I'm skeptical if that could be extended to include two-tone plating on modern nibs. (?) Perhaps heavy use of coarse paper to wipe the nib might degrade the plating, but I reckon that's a long reach.

 

Bye,

S1

[jar]

I guess I am just trying to find justifications about buying the Pelikan M800. My heart says "Go get it!" while my head says "No". LOL

 

Anyhow, I read that for a nib 14k is actually better than 18k. Is that true?

 

Gotta ask for a pause here.

 

Flexibility in a pen point is relatively complex and includes both the ability for the tine to spread but also that they then return to the original state.

 

In the past this was achieved through design, material and tempering. Gold is basically very soft and malleable and so exhibits the first trait (bends easily) but not the latter. You dent or bend gold and it stays bent or dented.

 

Regardless of what other metals are used in the alloy, more gold means softer end product. This is why fine jewelery rings are often 9ct or 10ct; they are harder and so less prone to scratching and denting.

 

For nibs, a range of gold content between 50% and 75% seems to be the best compromise between durability and softness. Both can be made stiff as a nail or soft and very flexible. But it is the design and manufacture process of the nib itself rather than the material it was made from that determines flexibility.

[Mickey]

There seems to be more than a little confusion here. I'll try to clear up some of it.

 

The biggest difference between 14K and 18K gold in nibs is (typically) not flexibility by plasticity, the tendency to permanently deform. All other thing equal, an 18K nib is more flexible, but also more plastic and likely to deform permanently when flexed, but all things are seldom equal. Because 18K is more prone to deformation, 18K nibs are often thicker and thus firmer than 14K nibs. Put another way, because most 14K alloys used in FP nibs spring back better than most 18K alloys, 14K nibs can be made thinner and thus more flexible.

 

The make up of the alloy has a great effect on flexibility and springiness. All 14K alloys are not equally flexible nor necessarily more flexible and springy than all 18K (or higher gold content) alloys.

 

Method of manufacture greatly affect the flexibility and springiness of the nib. Tempering, annealing, method of forming (cast, forge, roll, etc.), and plating all affect the performance of the nib.

 

Finally, the geometry of the nib is probably the most important factor. If the nib was not designed to flex, it should not be flexed and will not likely behave well is mistreated.

Edited March 19, 2014 by Mickey

[martinbir]

Getting back closer to the original question -

 

I am fortunate enough to have both an M600 with 14K nib (2yrs old) and an M800 with 18k (5-6yrs old).

 

In use the 14K nib seems softer and generally more pleasant to use. If you want an M800 justify it on the basis that it is the true Souveran with other models there to make up a range and has a solid brass piston mechanism.

 

As we all know, where there is a will, there is a way to justify it!

[ANM]

Gold does NOT flex. It is soft and will bend but not flex. Whether or not it can flex or be stiff depends on alloys in the gold and geometry of the cut.

[richardandtracy]

The engineering behind getting a certain degree of flex is surprisingly difficult, and making a life prediction for a nib is close to impossible. The factors that need to be considered for an analytical approach are the following:

• Desired stiffness (deflection for a specific applied load).
• Alloy composition
• Yield and ultimate strength of the alloy.
• Work hardening of alloy used.
• S-N curve for the alloy, which gives fatigue cycles to breakage for a particular alloy at various stresses
• Geometry of the nib

For any given alloy there will be a basic stiffness (Youngs Modulus, E) of the alloy. This will be lower for a higher gold content (eg 18k compared to 14k), as gold has one of the lower Youngs moduli of most metals. This would indicate that it will be more flexible for a higher gold content. However, at the same time, with the higher gold content the yield stress (the stress at which permanent deformation occurs) decreases, making it deform permanently at a lower stress. Whether the nib flexes and springs back as the gold content increases is dependant on the actual ratio of the Youngs modulus reduction to yield stress reduction - which can only be deduced by test.

 

To make life even more difficult, when you work harden a metal, the yield stress increases (if it reduces, this is called work softening and can be seen with many high copper content alloys). The ultimate breaking stress usually increases a bit with work hardening, but not by as much as the increase in yield strength. The net effect of work hardening is to enable a nib to flex more before it bends permanently, but gives you less room for error between bending it permanently & breaking it.

 

The geometry of the nib will have a significant effect on the flex. Imagine a flat sheet nib. As you lengthen the nib, the deflection is proportional to the cube of the length. The deflection is inversely proportional to the cube of the nib thickness and also inversely proportional to the Youngs modulus. While the stress is inversely proportional to the square of the thickness. Now, as you bend the flat sheet, the geometric stiffness (in engineering terms, the 'second moment of inertia' or 'I') increases rapidly, but depending on the geometry, the stress at certain points can increase by a greater or lesser degree. So, stiffening the nib by bending a flat sheet to the wrong proportions can actually reduce its strength by creating geometric stress concentrations. The ratio of the length of the slit to the length of the nib has a significant effect too. The slit means that the two sides work independently of each other, and in effect the depth of curvature of each side is halved, however as the stiffness is inversely proportional to the cube of the depth, the parts of the nib below the slit are only 1/8 the stiffness they would be if the slit were not there - which is why the Noodlers flex nib has a slit that extends into the section, it's a way of compensating for using stiff steel instead of flexy gold.

 

Anyway, at this point in the design it should be possible to make a prediction of the force needed to produce a certain level of flex, but how long will it last?

That is the question that is almost impossible to answer, as the s-n curves would have to be created by test for the alloy. Having done this, an estimate of the usage cycle of the pen would have to be made before a cumulative damage analysis could be made of the nib. Having done that... the flex design process for that alloy would be complete.

 

Where does this get us?
Almost nowhere. Sorry for wasting your time. It's just a consideration of all the factors affecting flex and damage to the nib, but in the absence of actual test data to particular alloys and particular nib geometries it cannot go anywhere.

 

Regards

 

Richard

Professional mechanical engineer and sometime stress engineer.

 

[Mickey]

The engineering behind getting a certain degree of flex is surprisingly difficult, and making a life prediction for a nib is close to impossible. The factors that need to be considered for an analytical approach are the following:

• Desired stiffness (deflection for a specific applied load).
• Alloy composition
• Yield and ultimate strength of the alloy.
• Work hardening of alloy used.
• S-N curve for the alloy, which gives fatigue cycles to breakage for a particular alloy at various stresses
• Geometry of the nib

For any given alloy there will be a basic stiffness (Youngs Modulus, E) of the alloy. This will be lower for a higher gold content (eg 18k compared to 14k), as gold has one of the lower Youngs moduli of most metals. This would indicate that it will be more flexible for a higher gold content. However, at the same time, with the higher gold content the yield stress (the stress at which permanent deformation occurs) decreases, making it deform permanently at a lower stress. Whether the nib flexes and springs back as the gold content increases is dependant on the actual ratio of the Youngs modulus reduction to yield stress reduction - which can only be deduced by test.

 

To make life even more difficult, when you work harden a metal, the yield stress increases (if it reduces, this is called work softening and can be seen with many high copper content alloys). The ultimate breaking stress usually increases a bit with work hardening, but not by as much as the increase in yield strength. The net effect of work hardening is to enable a nib to flex more before it bends permanently, but gives you less room for error between bending it permanently & breaking it.

 

The geometry of the nib will have a significant effect on the flex. Imagine a flat sheet nib. As you lengthen the nib, the deflection is proportional to the cube of the length. The deflection is inversely proportional to the cube of the nib thickness and also inversely proportional to the Youngs modulus. While the stress is inversely proportional to the square of the thickness. Now, as you bend the flat sheet, the geometric stiffness (in engineering terms, the 'second moment of inertia' or 'I') increases rapidly, but depending on the geometry, the stress at certain points can increase by a greater or lesser degree. So, stiffening the nib by bending a flat sheet to the wrong proportions can actually reduce its strength by creating geometric stress concentrations. The ratio of the length of the slit to the length of the nib has a significant effect too. The slit means that the two sides work independently of each other, and in effect the depth of curvature of each side is halved, however as the stiffness is inversely proportional to the cube of the depth, the parts of the nib below the slit are only 1/8 the stiffness they would be if the slit were not there - which is why the Noodlers flex nib has a slit that extends into the section, it's a way of compensating for using stiff steel instead of flexy gold.

 

Anyway, at this point in the design it should be possible to make a prediction of the force needed to produce a certain level of flex, but how long will it last?

That is the question that is almost impossible to answer, as the s-n curves would have to be created by test for the alloy. Having done this, an estimate of the usage cycle of the pen would have to be made before a cumulative damage analysis could be made of the nib. Having done that... the flex design process for that alloy would be complete.

 

Where does this get us?

Almost nowhere. Sorry for wasting your time. It's just a consideration of all the factors affecting flex and damage to the nib, but in the absence of actual test data to particular alloys and particular nib geometries it cannot go anywhere.

 

Regards

 

Richard

Professional mechanical engineer and sometime stress engineer.

 

 

Nicely done.

[Bo Bo Olson]

Both Richard and Mickey did a good job here.

 

The modern 800 from what everyone tells me is a nail. That being so, there was no need to test one in the B&M.

Steel nail, 14 K nail, 18 K nail...no difference.

Now if you want an 800 with a "good" nib, I trans-mailed a '87-89 800 to someone. That had a real nice springy nib....probably a 14 K then. Didn't mark it down in memory. Did mark down I'd buy that pen...even if I'm not much into Large pens.

 

My modern 605 is a semi-nail... others complain about the modern post '97 M400 has also a semi-nail...like a P-75...one of my other semi-nails.

I have a '90's M400 with a very nice vintage style springy regular flex nib...it is said by those with both that the '83-89 nib is a tad more springy....so I'd expect '90's 800 to also have a nice springy nib, as good as my '90's 400.

 

So the choice is simple buy a modern nail 800......if so Townsend makes a nice nail...IMO a nail's a nail. To be had everywhere. I am not prejudiced against nails...I got five or six....IMO only need four--.5...EF, F, M & B. and a CI in M-B....yep. For a CI or Stub a nail makes sense.

 

Or Buy a '87-89 used for not as much as a new 800, or buy a '90-97 800 and have a nib even if 14 K, that is a real nice springy regular flex.

It all depends on what you want the nib to do....sit there all 'butter smooth' and nothing else or something with a bit of life to it.

Edited March 19, 2014 by Bo Bo Olson

[Nokin]

The OP never mentioned flex at all in his post, only durability. I have the M800 with a 14c nib, and with the 18k nib. I also have a Sailor KOP with a 21K nib. They will all give me a lifetime's use, providing they are not mistreated. My own thought would be to choose the pen that feels most comfortable to use - personally, I find the M2XXs too light and small, and the M8XXs ideal. The OP may find the opposite is true, and the M800 too large? If possible, 'try one for size', and if it suits, go for it. Don't be put off by 14K vs.18k - go for what you enjoy writing with.

[proton007]

Both Richard and Mickey did a good job here.

 

The modern 800 from what everyone tells me is a nail. That being so, there was no need to test one in the B&M.

Steel nail, 14 K nail, 18 K nail...no difference.

Now if you want an 800 with a "good" nib, I trans-mailed a '87-89 800 to someone. That had a real nice springy nib....probably a 14 K then. Didn't mark it down in memory. Did mark down I'd buy that pen...even if I'm not much into Large pens.

 

Pelikan's single tone 18k nib (87-90) is pretty soft, softer than the 14k nibs in the pens of the same era.

 

I won't say durability is an issue, unless one uses too much pressure while writing.

[owend]

I have sevaral pens, among them two with gold nibs (14K), two with gold-plated steel nibs, two with natural-finished steel nibs. One gold nib is a Parker 61, hooded and rigid and almost invisible! The other is a Platinum PTL-5000 (14K). The Platinum is a deeper and more beautiful colour than the gold-plated steel nibs (Sonnet and M200) which look somehow matt and lesser quality although both still look good, so the solid gold wins on aesthetics.

 

For writing, the Platinum is noticeably more flexible, but the Sonnet and M200 are smoother and more satisfying writers.

 

From my limited sample, solid gold looks better, but the metallurgy in the nibs and the finish to the writing tip are more important for the writing experience. As I understand from various postings on FPN plus my A-level physics, metals can be made as springy as needed by what other metals are added (ie what make-up of alloy) and how they are treated. I've also seen several comments, noticeably about Pelikans, to the effect that the gold nib option may look better but are little different to, and sometimes not as good as, the gold-plated steel - I can't say from personal experience, never having tried a gold-nibbed M200.

 

I also got a Hero 725 for about £10 new from China, advertised with a solid 18K two-tone nib. The nib looks lovely but only writes when it feels like it (on a full moon when there's a Q in the month).

[haldane3]

 

It's solid gold. My M250 has 14k solid gold nib, and the M800 has 18k solid gold nib as well (mixed with rhodium I believe). I have no complaint about my existing pen, but I am just concerned that if I were to buy the M800, the new pen may not be as practical and as durable as my existing M250 pen. After all, M800 costs quite a bit of money, so I need a second opinion whether it worth the extra cost. There is no point paying that amount of money for 'inferior' pens.

 

It is worth the extra cost. It has a nicer heft, size, and an 18k nib which I personally find softer in general than 14k nibs. Buy it!

[Pelikan Vera]

I would think they are equally durable if you take care not to spring the nib. If it takes your fancy go for the larger pen.

[Bo Bo Olson]

Odd, I never think of Durability with my Pelikans....my 100n has lasted 65-70 years...500 (fancy 400) - 62-60..400n 59....400nn 58 in I have the rare '56 friction feed. my 140's close to that.

 

Yep, Pelikan is rather durable...his 800 should last until they stop making paper to write on....say 50-60 years. Longer if he leaves his grandchild a good stock of good paper.

 

Big difference between semi-vintage or vintage 14 K nibs with a bit of spring...and harder modern 14 K semi-nails. Like comparing apples and pineapples.

 

One should try pens with real nibs the semi-vintage pre '98-83 springy regular flex, or pre'66 vintage semi-flex or 'flexi'/maxi-semi-flex nibs, before committing to a modern 18 K nail.

That's a hell of a lot of money to give out for a nail.

 

My Lamy Persona 18 K OB nail stayed in the box until Pendelton Brown made it a CI. Now it's always in rotation.

That is a good thing to do with a modern nail. CI or Stub.

 

A modern 18 K may be "softer" in a nail??? than a 14 K semi-nail?

Perhaps some other brand?

Edited March 19, 2014 by Bo Bo Olson

[UK Mike]

I am a qualified metallurgist and materials engineer, but I'm not going to cloud matters with lots of data about the materials concerned or their method of fabrication, because in this case it doesn't matter as we are comparing an older Pelikan with a new M800.

It has been correctly stated that the "iridium" ball is what you are actually writing with, so the material of the nib has little or no relevance on the durability of the nib.

 

However, older Pelikan nibs had a degree of flexibility which is just not present in their modern offerings. I have a 50 year old Pelikan that has a lovely gold nib, steel M200s that have a little springiness, M400s and M600s that have a cushioned writing experience - and a modern M800 that is hard, unyielding and has less character in its nib than a $10 Jinhao from China. Yes it is smooth, and looks luxurious, but it isn't a favourite pen - which is a crying shame.

[Opooh]

Odd, I never think of Durability with my Pelikans....my 100n has lasted 65-70 years...500 (fancy 400) - 62-60..400n 59....400nn 58 in I have the rare '56 friction feed. my 140's close to that.

 

Yep, Pelikan is rather durable...his 800 should last until they stop making paper to write on....say 50-60 years. Longer if he leaves his grandchild a good stock of good paper.

 

Big difference between semi-vintage or vintage 14 K nibs with a bit of spring...and harder modern 14 K semi-nails. Like comparing apples and pineapples.

 

One should try pens with real nibs the semi-vintage pre '98-83 springy regular flex, or pre'66 vintage semi-flex or 'flexi'/maxi-semi-flex nibs, before committing to a modern 18 K nail.

That's a hell of a lot of money to give out for a nail.

 

My Lamy Persona 18 K OB nail stayed in the box until Pendelton Brown made it a CI. Now it's always in rotation.

That is a good thing to do with a modern nail. CI or Stub.

 

A modern 18 K may be "softer" in a nail??? than a 14 K semi-nail?

Perhaps some other brand?

Richard binders opinion on flex for a 18 K nib

 

http://blog.richardspens.com/PenBlog/Sweepings_from_the_Studio/Entries/2009/1/15_Ya_gotta_be_flexible.html

[Water Ouzel]

Gold does NOT flex. It is soft and will bend but not flex. Whether or not it can flex or be stiff depends on alloys in the gold and geometry of the cut.

Sure gold will flex,as long as you don't exceed its elastic limit, which is much lower than steel alloys.