The result was a darker Havana Brown but in no way was the quality of the writing compromised. The Diamond 530 wrote as well as before, with the broad nib. As a parenthesis, I haven't used the original EF nib for a long time. Once I fell in love with the B nib I saw no reason to fall back on the EF.
Here's my TWSBI Diamond 530 disassembled into its basic parts.
I really like a fountain pen that can be broken apart as much as the TWSBI. It makes for easy and thorough cleaning, not to mention that you can learn more about the inner workings of the pen. I'm going to give a short description of each of the parts in this exploded view.
- Cap - it can be further disassembled by removing the inner screw that fastens the clip. I didn't have the correct tool for this so I skipped it.
- Inner cap - this little piece helps seal the nib inside the cap so that the ink doesn't dry. It is friction fit and can be tricky to remove, unless you know the trick. It's quite easy actually: take a pencil (preferably one with an eraser at the end), wrap an elastic band around the eraser, stick it inside the cap until you feel it squeezing tightly inside the inner cap, and the pull it out. It should drag the inner cap with it.
- Inner section - this piece holds the nib and feed together. It is keyed such that there's no chance of fitting the nib and feed in the wrong position. Notice that there's also a small o-ring there which I haven't removed.
- Outer section - it has 4 tiny grooves distributed equally on the inside. When you push the inner section inside it, make sure to match the grooves, otherwise this piece might crack over time. 3,4,5 and 6 form the nib unit.
- Barrel - it has another o-ring which seals the nib when the cap is screwed on. At the other end there's a metal inner collar with threads to which the piston mechanism is attached.
- Piston rod
- Piston holding thingy - sorry, don't know what this part is called but it screws on to the end of the barrel, counterclockwise. The piston rod goes through it.
- Piston activation thingy - this bit actually operates the piston rod. It has a spiral thread inside which fits the spiral on the rod.
- Piston knob - This screws on to #10 and actuates #11.
- Wrench - this comes with the pen and is used to remove #10.
So this is what makes the TWSBI Diamond 530 (and also the 540) tick. I apologize if I haven't named the parts correctly but I have no idea what the technical terms for some of them are. Now the tricky part will be to put it back up together!