An attempt at building a better pen
An attempt at building a better pen
I'm a fan of cheap and cheerful fountain pens
A few things bother me a little about those pens. Small reservoirs, tiny converters. Barrels not quite long enough, often top heavy with the cap posted. Or a cap that dances on the back
When young, I was taught to write with a fude brush : vertical position, fingers high on the barrel. I like to play with the position of my grip, and on most pens, the thread for the cap is in the way.
So I designed a pen that would solve all those problems. Tried to make it as simple as I could : a controlled leak, a reservoir, a simple way of filling said reservoir, in a shape that is a pleasure to write and draw with.
And the cap should make a water-tight seal around the nib.
Bought a mini-lathe, some perspex rod, and started building.
First, I tried my hand at triple entry thread. I wanted a cap that would close in two thirds of a turn. One turn in 3 mm, thread profile is 1mm wide, nearly half a mm deep, and for the cap, I cut 2 mm of thread.
I'm lazy, didn't want to change the thread gearing, so I used the same pitch for the piston and the back cap.
Here is the piston fitted to the section-body. The body and piston together can contain about 4 ml of ink. Not bad. The piston alone fills with more ink than a standard cartridge.
Drilling operations were a real pain in the derrière. Drill bits heat up very fast, and then the plastic melts. I ended up drilling 3 mm at a time, starting with a 4 mm drill, and then stepped up half a mm at a time, up to size.
Some of these cavities took a whole day to bore. Talk about boring.
All the roughed out pieces: at the back, from left to right: the piston plunger with its o-ring, the cap, the body or section. In front: the ring that keeps the plunger in the body, and the back cap.
Setting up for cutting the tapers: 1 over 19 mm. About 2 degrees per side.
And here it is, my first flawed, but working pen:
A bit longer than a MontBlanc 149, especially uncapped. Thread is at the end of the section, which tapers up from 11 mm to 16mm, but the fat part is rather far back: it is comfortable in the hand, and I can put my fingers anywhere I want.
The back cap has the same taper, so the cap fits perfectly when posted. The barrel extends about 2 cm below the cap, so it is easy to not unscrew the back cap, and if you do, there is more than enough grip to unscrew the cap itself. It has a hole in the feed, that retains a 1,5 mm tube, mounting up into the piston. As in the converter in Nooders' Ahab fountain pen, this ensures that the reservoir is filled in two or three pulls. As the pen is very light, filling it makes a significant change in its balance. I think the ink may weigh as much as the pen. One advantage of having the thread for the cap at the end of the section, is that it is (relatively) easy to build an ink-bottle cap in which you can screw in the pen, turn everything bottoms up, and fill like a syringe. An o-ring at the end of the thread should keep everything waterproof.
It is generous with ink. I fitted it with a nr.6 flex nib and matching ebonite feed, and it writes really wet. I like that. No railroading. Don't mind inky fingers.
Lots of mistakes and Bozo moments. After drilling most of the holes, I found out that when the headstock is misaligned, you get helicoidal holes. I discovered too late that my drills cut a hair undersize, so all my inside threads are too small. Had to shave a smidgen off the outside threads. When mounting the back cap in the four-jaw, for cutting the taper, I was too careful about not compressing the thin, threaded part (only 10 mm of straight, before the taper begins), and the part broke loose, made four cracks. I was only cutting a 10th of a mm.
I learnt a lot of lessons. The next one will be a lot better. The biggest lesson I learnt is that turning a pen, from scratch, is a hard, patient slog, and an expensive endeavour. If I were up to production speed I could, maybe, turn a pen in 40 or so hours. If I wanted to live off making pens, I'd have to go hungry to make them way over-priced. I have a few ideas to make the production less onerous. I could mould resin over the inside shapes, and then turn off the outsides. Happily, the inside and outside thread at the back of the body have the same pitch, so it should be possible to make moulds that allow the cured parts to unscrew easily. But pouring resins can be a stinky business, and I would need something to get rid of air bubbles. Who wants holes in their threads?
I'm going to call it 'Le Piston'.
Thank you for enduring this whale of a post. I hope the pictures will make you forgive me
Cheers
Lukas
