Easing the tight fit of a nib and feed -- sand down the feed?

[Paul-in-SF]

I have come into possession of a Parker striped Duofold with a Vacumatic filler. It came with the wrong feed (and possibly the wrong nib, it has an arrow on it and it says "51" which if it is a date code means it is after they stopped doing the striped Duofolds, if I understand correctly, but otherwise it seems about the right size). They are, in combination, very slightly too thick to fit all the way into the section; they stick out far enough that the cap of the pen doesn't fit on properly. 

 

I found a spare feed in my parts box that is the right size, but sadly it has no hole for a breather tube, so I fear it would not take in ink. The difference in thickness is quite small, 0.03 mm by my digital calipers (5.96 mm vs. 5.93 mm for just the feed). I have thought of rolling the feed in some sandpaper to reduce the diameter (ok, I actually tried it with my coarsest micromesh, 3200, but all it did was make it shiny). So have any of you tried to reduce the thickness of a feed while keeping it round, and if so, please share your tips and tricks. Or share your suggestions for a different solution. 

[mhguda]

With some ebonite feeds, that has worked for me. I tried to keep the correct shape by spending the same amount of time everywhere, so going around the feed in small increments and repeating if it turned out not to be enough.

I used nr 2000 sandpaper. Nailbuffer also worked.

Once done, rinse it down and maybe scrape out the main channel, just to make sure there's no debris left from the sanding.

 

I have no idea if this works with plastic feeds, but with ebonite, by now, it's a no-brainer for me.

[OMASsimo]

I just had to do this with a Soenecken ebonite feed because the celluloid section had shrunk. As @mhguda wrote, it works fine for ebonite feeds if you go about it carefully in small steps. 0.03 mm won't take very much of sanding and what's gone is gone. It might work for plastic feeds as well but it might depend on the type of plastic what's the best procedure. I think there's only one way to find out. Good luck and stay patient.

[Paul-in-SF]

I should have mentioned that I assumed it was an ebonite feed, but now I'm not certain. I'll try to get some decent photos to post. 

 

Edited to add: here are the photos. 

[mhguda]

It does look like one, but maybe you will be able to tell: can you smell it? Ebonite has a very distinctive smell when rubbed.

[Paul-in-SF]

3 hours ago, mhguda said:

It does look like one, but maybe you will be able to tell: can you smell it? Ebonite has a very distinctive smell when rubbed.

Maybe, if there a smell it's very faint. Maybe my nose is insensitive. Or maybe the smell has gotten weaker after 70 years or so. 

[mhguda]

I think I'd risk it.

[Paul-in-SF]

Thank you, I did risk it, using the only very fine sandpaper I had, which was 320 grit. I rolled it gently within a folded piece, taking it a little at a time, and found it was still a bit out of round before I'd gone too far (fortunately) so I was able to compensate by taking a tiny amount off the sides, and voilà - the nib and feed fit snugly and now can go as far into the section as they are supposed to. 

 

I wasn't able to test the vacumatic filler before, but it took in ink (not sure how much at this point) so it is now on writing rotation. 

 

I appreciate everyone's help and encouragement. The pen was a pretty good bargain, and it always makes me feel a bit chuffed to get a pen working that wasn't before. 

[OMASsimo]

Congratulations! And I’m glad for another salvaged pen.

[mhguda]

Thanks for the update and yes, I know that feeling. So congratulations! and enjoy another pen brought back from nonfunctioning...

[Paul-in-SF]

20 hours ago, Paul-in-SF said:

Maybe, if there a smell it's very faint. Maybe my nose is insensitive. Or maybe the smell has gotten weaker after 70 years or so. 

I forgot to mention, when I used sandpaper on the feed, the smell did get stronger, so I expect it is ebonite.