This article has been inspired by the forum Experiments With Flex on the Fountain Pen Network website. My ingeneer’s mind was stimulated by the methodical composition of experimentation, and the valuable contributions by the visitors made this forum a lively experience. This motivated me to write this paper.
After an initial discourse on the definition and classification of flex‑nibs, I introduce the mechanics of nibs with particular emphasis on flex‑nibs. Then follow chapters on the practical application of such findings. Finally, I respond to visitors’ comments on the forum when I consolidated their discoveries with ingeneering information.
Outline of Paper
Let’s start with an introduction to the structure of this paper. After an initial discourse on the definition and classification of flex‑nibs, I introduce the mechanics of nibs with particular emphasis on flex‑nibs. Then follow chapters on the practical application of such findings. Finally, I respond to visitors’ comments on the forum when I consolidate their discoveries with ingeneering information.
A clear structure helps me to sort out where what belongs, and it helps you find what you are interested in. Embedded in the Headings are links to the main chapters. I added the titles to the sub-chapters underneath the summary.
When reading some forums on the Fountain Pen Network, I noticed that there is a multitude of most romantic descriptive expressions for the various styles of fountain pen nibs, such as “Wet Noodles” and the opposite “Nail”. Experienced flex‑nib writers have surely a sense the meaning, but I also noticed the confusion these expressions cause, especially amongst novices, like me.
Chapters: 1. All Nibs Flex (What is flex?) — 2. All Nibs are preloaded — 3. What’s the Difference? (various write scenarios) — 4. Types of Flex Nibs (findings of the web)
Here I investigate and comment on two suggestions of classifying nibs according to their technical parameters. I conclude with a proposal of my own, with the hope that it will find the flex-writers’ acceptance.
Chapters: 5. Technical Approach (Investigation and analysis of a test method) — 6. Useful Line Width (How far can the tines be separated and the nib still produces a full line) — 7. Useful Writing Pressure (Comfortable writing pressures)
A synthesis of what I learned from the above measuring methods including my own ponderings.
This is an ingeneering approach to the function of flex‑nibs, an introduction to the principles of the mechanical physics of bending, the nib’s shape and material and the suggestions of expressions on nib characteristics. You may be aware of the chapters on standard nibs pertaining to these topics. Nib Materials and Nib Mechanics.
Chapters: 9. When one applies Sufficient Force (… anything can be bent, Force vector diagrams on nibs) — 10. Spreading of Tines (Why do the tines open when force is applied to the tip of the nib?) — 11. Bending (Basics on bending) — 12. Bending of a Profile (about bending moments and the effect of shape)
In this section, I apply the basics from the above chapter (the technical side) to the characteristics of nibs as they are determined by their dimensional details. Comparisons are made between nibs after their dimensions have been calculated or graphically established and their actual behaviour when attached to a fountain pen.
Chapters: 13. Variation of the Theme (application of the basics on dimensionally detailed nibs) — 14. Permanent Damage (A refresher on Stresses and Strains) — 15. Nibs are not flat (discussion on the effect of curving a nib) — 16. Effective Dimensions (How to establish the dimensions, which influence a nib’s performance.)
As the title suggests, here I respond to some technical discussions in the forum on Experiments With Flex. They cover aspects of adding or increasing the breather hole or adding scallops to the side of nibs. I also include here a discussion on the function of flat tines.
Chapters: 17. A – Increasing of the Breather Hole — 17.B – Wing Scallops — 17.C – Long Slit and Breather Hole — 17. D – Radius of Nib Curvature — 17. E – Thinning Nib — 17. F – Shape and Position of Scallops — 17. G – Mating Nibs and Feeds — 17. H – Underside of the Nib — 18. Hole versus Scallops (What’s more effective?) — 19. Flat Tines (Samples of flat nibs, how they work and how beautiful they are)
G – Finale (Thanks and acknowledgements)
Above all: Enjoy!
Continue reading the first chapter titled 051-7-1 Definitions of Flex 1–4