The Pilot Petit1 is an amazingly versatile pen--it writes like a pen three times the price, comes in a rainbow of colors, and fits in your pocket. But at only 4.2" long, it's limited when it comes to ink capacity, and isn't compatible with any converters (so you can't use your vast collection of bottled inks).
Fortunately, you can more than triple the ink capacity from 0.6mL to about 2mL by performing a simple eyedropper conversion, which turns the whole barrel into an ink reservoir. Basically, you will be removing the ink cartridge that comes with the pen, filling the barrel with ink, and screwing the pen back together with the help of some silicone grease on the threads (to keep the pen from leaking).
The additional ink will alleviate any concerns about running out of ink mid-meeting, and it looks pretty cool, too. Here's how to do it:
1. Disassemble the pen and remove the ink cartridge. You can tape the open end of the cartridge to save it for later.
2. Flush nib with water until it runs clear, then gently wipe dry.
3. Coat threads with a layer of silicone grease. The grease repels liquids (like ink), making an impenetrable seal.
4. Fill the barrel with ink using the eyedropper.
5. Screw the pen back together with the nib pointing up.
6. Wipe off excess grease.
After you've completed the conversion, pause to admire your turbo-charged Petit1, get the ink flow going on a piece of scrap paper, and you're good to go!
Generally, the rule of thumb is to refill an eyedropper pen once it's two-thirds empty. This is because the warmth from your hand or pocket can cause the air in the pen body to expand, pushing unwanted ink out through the nib onto the cap or paper. You should also carry the pen nib up to avoid leaks.
Note: If you're feeling leery about the eyedropper conversion, or just prefer using cartridges, you can also simply refill used/spare ink cartridges with an ink syringe. Draw ink from the bottled ink of your choice, insert the syringe into an empty cartridge, and depress the plunger slowly to fill. It's best to aim at the side of the cartridge (like with beer and soda) so that bubbles don't form.
Now that you've performed a successful eyedropper conversion on the Pilot Petit1, try to write with it all day to gauge how much ink you're using. If you're still running out too quickly, you might want to convert a standard size fountain pen--like the Platinum Preppy Fountain Pen or Pilot Prera Fountain Pen. Watch out for cracks in plastic pens before you start, but otherwise, go for it!
Share your eyedropper conversion tips, tricks, and experiences in the comments!