The first Double Flat S

The first fountain pen that came out of my lathe was the one I called Double Flat S. The S is the size. We'll have Double Flat S, M and L. I'm pretty sure we also will see  XL.

The measurements of these and all series will be (without cap):

• S: up to 125mm / 4.9"
• M: up to 130mm / 5.11"
• L : up to 140mm / 5.51"
•  XL: from 140mm / 5.51" upwards

It's made from a material called Casein. This one in particular is called Yellow Tiffany Casein and comes directly from the UK.

I didn't really expect such spectacular material when I got the blank... 

I like simple fountain pens. Not so much golden or trims. This does not mean that I do not experiment with them throughout the learning process.

The Flat Double has no clip, they are smooth with flat ends.

In this case we start from a couple of casein sticks. Brief explanation. Casein is obtained from milk. in this very common product, there are proteins called casein, and from a chemical process different products are obtained. One of them is a type of polymer called casein.

The product that comes to us is the so-called Yellow Tiffany Casein, produced by The Turners Workshop.

The result is this:

Characteristics:
Material Body: Casein
Metals: NO
Cap: Screw on
Nib: Jowo nº5 Fine Steel 
Filling system: Universal Cartridge
Length (capped): 128mm/5.03" long
Length (uncapped): 120mm/4.72" long
Length (posted): N/A
Diameter (body): 11.5mm/0.45".
Diameter (cap): 13.2mm/0.52" diameter

This was my first pen and I found some mistakes that I should improve on:

•  The plug thread to the body is too long. one has to go around too much
•  I wanted to make the connection of the section to the body under pressure, without thread due to the small size of the pen. over time, it's gotten big