TWSBI Leaking at the Nib

[itsonlybarney]

I have two TWSBI Eco pens at the moment that are leaking via the nib/feed.

I have loaded De Atramentis ink in both of them, one red and one blue. The blue appears to be slightly thicker than the red, but I'm having trouble with both of them.

I have tried the following steps to try and work out what is the problem:

1. cleaned / flushed both the nib, feed, and the pens

2. vacuum test to see if they are leaking air. Both will hang from my moistened finger tip for >30 seconds without showing any signs of air leakage

3. reseated the nib and feed firmly in the pen

They both write well when used, but at least or twice per day, each of them will leak a large drop of ink onto the page before I witness and attempt to catch it to stop it from dripping. Occasionally, I have caught it before dripping on the paper once or twice, and ink appears to be pooling all around the feed within the nib on the sides.

My gut says that there is a larger than expected gap between the nib and feed, OR there is air leaking around the side of the feed rather than through a crack in the barrel.

Any suggestions for a solution?

Right now I'm thinking maybe coating the inside of the feed holding part of the barrel with lube before inserting the feed/nib to plug any "holes" that may be leaking air up the side.

[Claes]

>My gut says that there is a larger than expected gap between the nib and feed

 

That was my first thought as well.

What if you put the back of the pen (cap off and nib pointing downards) inside your mouth,

close your lips around it and blow? Are any drops forced out?

 

Have fun1
Claes in Lund, Sweden

[itsonlybarney]

On 6/23/2025 at 9:44 PM, Claes said:

What if you put the back of the pen (cap off and nib pointing downards) inside your mouth,

close your lips around it and blow? Are any drops forced out?

As in loosen the plunger slightly, and see if I can blow through the plunger? 

[Claes]

Actually, first try with fastened plunger. Then with plunger button loosened just a trifle, i.e. not so much that the plunger moves.

[itsonlybarney]

On 6/25/2025 at 11:26 PM, Claes said:

Actually, first try with fastened plunger. Then with plunger button loosened just a trifle, i.e. not so much that the plunger moves.

Tried that, no leakage at all. I'm starting to think I may be pressing hard on the nib and have bent it slightly, only becuase it leaks into the lid without any pressure occasionally. 

[Claes]

Good.

Is there a wide gap between the tines? Or just a narrow one?

Have you checked the distance between the top of the feed and the underside of the nib?

Can you insert a piece of paper between the feed and the nib?

 

Have fun!
Claes in Lund, Sweden

 

[Beechwood]

On 6/23/2025 at 12:32 PM, itsonlybarney said:

I have two TWSBI Eco pens at the moment that are leaking via the nib/feed.

I have loaded De Atramentis ink in both of them, one red and one blue. The blue appears to be slightly thicker than the red, but I'm having trouble with both of them.

I have tried the following steps to try and work out what is the problem:

1. cleaned / flushed both the nib, feed, and the pens

2. vacuum test to see if they are leaking air. Both will hang from my moistened finger tip for >30 seconds without showing any signs of air leakage

3. reseated the nib and feed firmly in the pen

They both write well when used, but at least or twice per day, each of them will leak a large drop of ink onto the page before I witness and attempt to catch it to stop it from dripping. Occasionally, I have caught it before dripping on the paper once or twice, and ink appears to be pooling all around the feed within the nib on the sides.

My gut says that there is a larger than expected gap between the nib and feed, OR there is air leaking around the side of the feed rather than through a crack in the barrel.

Any suggestions for a solution?

Right now I'm thinking maybe coating the inside of the feed holding part of the barrel with lube before inserting the feed/nib to plug any "holes" that may be leaking air up the side.

 

 

I have had all the same problems with my Ecos, it is very frustrating. I put it down to my having taken the feed out in the manner suggested by TWSBI.

 

Firstly, check the section for cracks caused when the nib and feed were put back, if no cracks you can help the situation after filling by only filling part way, hold the pen nib uppermost and pull air into the pen, then dry the nib and feed with a cloth.

 

There is also only one precise position for the nib to fit on the feed. This is not made clear on the TWSBI instructions.

 

To be honest, I gave up on these pens and I haven't used them in years,  just more trouble than they were worth.

[Misfit]

Get a paper towel. Grasp the nib In the paper towel between your thumb and index finger. Let go. Hopefully that stops this. 
 

Do you remember after filling to let a drop or two of ink out? It’s in the TWSBI instructions. 

[MartinTenbones]

I have been asked to fix a few leaky ecos I'm the past.  The nibs go back one way as the end of the feed is keyed.  The nib and feed feels like it seats no matter which way you put it in but there really is only one way it goes all the way. 

 

If you can see the nib size visible on your nib it is most likely not in correct.  When they are in properly the nib size is hidden inside the nib section. 

[itsonlybarney]

On 7/4/2025 at 7:40 PM, Claes said:

Is there a wide gap between the tines? Or just a narrow one?

The pen writes well, the tines appear the same as with other pens that don't seem to have this problem. 

 

Quote

Have you checked the distance between the top of the feed and the underside of the nib?

Can you insert a piece of paper between the feed and the nib?

What is the best way to do that? I have tried to make sure that they are sitting as close together as possible, but it still happens after this.  I haven't tried inserting paper, will try this.

 

 

[itsonlybarney]

On 7/4/2025 at 8:04 PM, Beechwood said:

 

 

I have had all the same problems with my Ecos, it is very frustrating. I put it down to my having taken the feed out in the manner suggested by TWSBI.

 

Firstly, check the section for cracks caused when the nib and feed were put back, if no cracks you can help the situation after filling by only filling part way, hold the pen nib uppermost and pull air into the pen, then dry the nib and feed with a cloth.

 

There is also only one precise position for the nib to fit on the feed. This is not made clear on the TWSBI instructions.

 

To be honest, I gave up on these pens and I haven't used them in years,  just more trouble than they were worth.

It only seems to happen on pens that I have removed the nib & feed to properly flush out the pens/ink. So this is what I am attributing it to at the moment. These two pens are my daily drivers and get the most use as well.

 

What is the precise position that you are referring to? I did notice that there was a certain position with an "indent" that I could feel, and it only occured in one place throughout the 360 degree roatation. 

[itsonlybarney]

On 7/5/2025 at 1:11 PM, Misfit said:

Get a paper towel. Grasp the nib In the paper towel between your thumb and index finger. Let go. Hopefully that stops this. 
 

Do you remember after filling to let a drop or two of ink out? It’s in the TWSBI instructions. 

This is what I have been doing, squeezing the nib and feed together to try and close any gap once I worked out that it was coming from between the nib and feed. I'm also wondering if the gap opens up because occasionally I can be heavy handed on the tip. 

[itsonlybarney]

On 7/7/2025 at 5:08 AM, MartinTenbones said:

I have been asked to fix a few leaky ecos I'm the past.  The nibs go back one way as the end of the feed is keyed.  The nib and feed feels like it seats no matter which way you put it in but there really is only one way it goes all the way. 

 

If you can see the nib size visible on your nib it is most likely not in correct.  When they are in properly the nib size is hidden inside the nib section. 

I did find some "indent" position when I last flushed the pen and reinstalled the nib/feed. I just had a look at the pen, and probably 80% of the nib size is visible at the moment for the two pens that leak.  I looked at one of the others that isn't leaking and see about 20% of the nib size.

 

 

If this is the case, what is the trick to getting the nib to sit deeply? 

[MartinTenbones]

I've always looked inside and a lined it up that way.  Once you look at the back of the nib you can see which way the key is.  If I'm not mistaken it is aligned with the ecos nib section "triangle" section so you may be able to line it up by looking down the pen.   It only goes in one way so each point of the triangle may be the "top".   If you don't want to the the ink out you could always pull the ink back with the pison and leave  the ink in the pen.   

[MartinTenbones]

From the look of that photo the nib needs to turn to the left slightly.  I would pull it out first though instead of just turning it.  There is a lot of friction on that nib currently so just trying to turn it 1mm without pulling it could break the feed

[MartinTenbones]

The key is back here. 

 

 

[Beechwood]

TWSBI made a sales point about being able to disassemble the pen, whether or not you actually did need to take the pen apart, some people took the pen apart to see if they could.

 

I removed the nib and feed to clean a stained section, wish I had left it alone.

 

 

[itsonlybarney]

On 7/12/2025 at 10:50 PM, MartinTenbones said:

I've always looked inside and a lined it up that way.  Once you look at the back of the nib you can see which way the key is.  If I'm not mistaken it is aligned with the ecos nib section "triangle" section so you may be able to line it up by looking down the pen.   It only goes in one way so each point of the triangle may be the "top".   If you don't want to the the ink out you could always pull the ink back with the pison and leave  the ink in the pen.   

I had a look at one of my empty pens, and I couldn't distinguish the key that you are referring to. I already line up my nib so that it is parallel with the "bottom" of the triangular grip. 

 

On an empty pen I have, I did push the nib in against the feed step and 90% of the nib size letter is now hidden away. I haven't filled it as yet because it isn't my preferred nib size 

 

On 7/12/2025 at 10:57 PM, MartinTenbones said:

From the look of that photo the nib needs to turn to the left slightly.  I would pull it out first though instead of just turning it.  There is a lot of friction on that nib currently so just trying to turn it 1mm without pulling it could break the feed

I'm going to leave it for now, will look when I finish the current ink.

 

On 7/12/2025 at 11:39 PM, Beechwood said:

TWSBI made a sales point about being able to disassemble the pen, whether or not you actually did need to take the pen apart, some people took the pen apart to see if they could.

 

I removed the nib and feed to clean a stained section, wish I had left it alone.

I regret touching mind as well now, it has only been an issue on pens I have cleaned thoroughly.

[Beechwood]

5 hours ago, itsonlybarney said:

 

 

I regret touching mind as well now, it has only been an issue on pens I have cleaned thoroughly.

 

 

The advice was given on FPN not long after the Twsbi Eco was launched on the subject of taking the pen apart, 'just because you can doesn't mean that you should'.

 

That didn't stop anyone.