Cannon-Pen (safety-pen)

thingiverse

When I created my first safety pen, it looked a bit like a cannon to me, so I decided to make a pen that really resembled a cannon. The pen is called a safety pen, and it's the first fountain pen that wasn't prone to leaking in your pocket - a name that originated from this very feature. They were mass-produced from 1890 to 1940. Don't try to fill it if you're afraid of getting ink on your fingers; without experience, it's impossible (As you can see in the photos, I forgot to apply silicone grease to the TPU washer and ended up with a leaking pen). It's filled with ink using an eye-dropper or syringe. When carrying it around, use a cup to prevent the ink from leaking. To start writing, bring the pen into working order by keeping it vertically with the cup up, unscrewing the cup, and rotating the bottom to retract the nib. Once the nib is retracted, the ink won't leak, and you can write. Then, put the pen back in its upright position and rotate the bottom again to remove the nib (here's a problem - it might spit some ink around). Put the cup back on. To build this pen, you'll need: 1) A 5mm diameter nib with a feeder (the most complex part; you can find it mostly in old pens. I bought old Rifka modules on eBay, but the same diameter feed and nib were used in broken Montblanc and Pelikan pens that I purchased at a flea market). 2) A 1mm diameter rod (I have a carbon one from Conrad Electronics, but stainless steel or ebonite will work too). 3) A 1mm drill or a very precise printer that can print 1mm holes. 4) Two 3mm/1.5mm O-rings (mine came from a huge metric O-ring assortment kit - 10 euros on eBay). 5) Silicone grease. 6) A 1.75mm diameter filament cut. 7) Print or make a thin TPU or rubber washer to create the bottom watertight seal; only silicone grease is enough if you polish it well. P.S. The pen was created when I switched from FreeCAD to OpenSCAD, so most parts were made in FreeCAD, but the improved spiral and stand were designed using OpenSCAD. P.P.S. The idea of the mechanics came from an old safety pen, probably a Waterman.