Don't you just hate when the ink runs dry on your favorite pen and you run for the stock of re-fills only to find it won't fit properly in the pen. Actually, I'm like game on and start thinking of how I might solve this problem. The solution is not always the same but I am hoping to give some ideas by providing a specific example of retrofitting a pen refill to fit into a specific pen so writing can commence.
My pen is a brand new Grifit Dootle pen/stylus combination (pictured above with the twist-on cap removed) which I recently received after a sweet Massdrop to save money. My problem is that I am picky with the feel of my writing implement on the paper. The Dootle is designed to fit many common rollerball refills, specifically the Pilot G-2, Mont Blanc 512, Lamy 63, Waterman 011, Itoya MBR-5, or the Signo UMR IL7. My re-fill stock and preferred ballpoint refill was the Schmidt easyFLOW 9000 M.
Below is the process to make it fit nicely in the Grifiti Dootle so that I can get back to work!
Step 1: Gather the Tools
> Razor Blade Knife or another sharp cutting edge
> Measuring Device
Step 2: Take the Pen Apart
Disassemble the pen and organize the parts:
1. Unscrew the cap/clip portion (comes with the stylus tip attached).
2. Unscrew the metal end that holds the pen refill inside the Dootle.
3. Remove the spring and set it aside somewhere safe so it doesn't roll on the the floor and become the fascination of your greyhound.
4. The pen refill should also be removed, it might take a little push from the business end (where the writing occurs for the schlubs who spend all your time at the computer).
Step 3: The Problem
The rollerball re-fill supplied with the pen is on top in the picture and my preferred smooth Schmidt easyFLOW 9000 M ballpoint re-fill is on the bottom. The black collar to the left of the Schmidt re-fill is included with the re-fill to protect the tip and is a necessary part for the solution to the fit problem.
Notice the original re-fill has a shorter writing tip than the Schmidt re-fill does with a larger round portion a small distance above the writing tip (which the Schmidt re-fill doesn't). Since that round black tip protector included with the Schmidt re-fill fits snugly we will use a portion of it to emulate the enlarged area of the original re-fill. The other portion of the protector will be used at the other end of the re-fill when re-assembling the pen so don't feed it to the dog!
Step 4: The Solution
We are going to cut the Schmidt black tip protector into two pieces the will allow this re-fill to fit perfectly in the Dootle.
Step 5: Cutting the Adapters
Using a cutting tool like a razor blade knife and something to measure, cut two portions of the Schmidt round black tip protector. The pieces are shown above measured in metric and also in English for those of us Jimmy Carter lovers left behind in the US still struggling to deal with fractions, ugh! Be careful to get as straight a cut as possible. The sharpest tool is always the easiest to use (doctors in emergency rooms worldwide sponsored the previous statement).
Small piece: 5mm or 3/16 inch
Large Piece: 17mm or 21/32 inch
A nice web conversion tool for mm to fractions but you can always thumb your nose to American politicians and just always measure in metric!
Step 6: Add the Adapters to the Re-fill
Place the small adapter just cut over the tip of the Schmidt pen re-fill. Keep the larger one for pen re-assembly
Step 7: Pen Re-assembly
Put all of the parts back together. The re-fill into the pen, the large adapter next on-top of the insert, the spring, and screw on the pen metal top.
Step 8: Finished
Ready to write, put the cap on to use as a tablet or smart phone stylus, or place in your pocket protector for those excursions where geek is chic!