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| From top to bottom; Pilot Blue, Monteverde Green Emerald, and Noodler's Qin Sin Huang |
Blog Archive
Friday, October 17, 2025
Quick Paper Review: Life Bank Paper Notepad
Sunday, August 31, 2025
Gravitas Ultemvac with Platinum Broad nib Part 2
Putting the Platinum broad nib on

The Platinum 3776 Century broad nib is all its glory
In this part two, I will continue where I left off where I finally just put that Platinum 3776 Century broad nib into this Gravitas Vac Ultem, thanks to this Jowo-threaded custom housing I got from Flexible Nib Factory.
But regarding the default Gravitas medium nib, I mentioned I tried opening the tines a little and most of all, swapped the ink from Waterman Serenity Blue to Pilot Iroshizuko Asa-Gao. To my surprise, and while mild confusion, the nib is wetter and that alone improved the performance of the nib. If it really is the change of ink, then this Asa-Gao might actually be wetter and more lubricating than Waterman ink.
Unfortunately, I lost interest in it because the custom housing for my Platinum nib finally arrived, and I wasted no time to already friction-fit the nib and feed into the housing and then screw the entire unit into the Vac Ultem.
The Platinum broad nib was a slightly dry yet smooth nib that has this minor yet pleasure pencil-like feedback, that seems to be a common characteristic of Platinum’s nibs. I have it in broad tip size, but remember that Japanese nibs generally write a size smaller than Western nib sizes. So this broad nib has the line width of a typical Western medium nib.
Honestly, I do like it that way. I am not all that big on Western broad nibs due to the weird ball-like writing experience, and in addition, my most prefer tip size is at most a Western medium. Thus, this broad Platinum nib fits my preferences nicely.
Something I find worth noting, based on personal experience, this tip sure does look a little stub-like. Writing with the nib since I got it almost two years ago, I think it has a stub-like feel whenever it put the nib tip to paper and write. The feel of the downstrokes like a wide surface area of the tip, and vice versa, with horizontal strokes feeling like having a thinner surface area being in contact with the paper.
Do note, I have yet to fully experience an actual stub nib, like the 1.1mm or 1.5mm nibs from Jowo. But when writing with this Platinum nib, I sometimes confidently question whether I should call it, a stubby nib.
Now I put the nib is in this custom housing, and already, I say this looks good. Most importantly, the pen, and the nib, writes still wonderfully. The first thing to notice, it seems to become much wetter somehow, and thus smoother. That Platinum feedback also became a little more subtle here. I am not for sure if it has to do with the custom housing or that the nib is now in a vacuum filling body.
I would say I would prefer it kept that feedback it normally had. But yet again, this is still an amazing writing experience. Additionally, the larger ink reservoir, a more interesting filling system and a larger grip section for comfort are great for any small trade-offs. So far, at least compared to the Platinum nib being in its original pen body.
Just a quick note; when I tried putting the Platinum nib and feed into the custom housing, it is, of course, friction fitted. But it was also a tight fit. I almost became hesitant for fear of potentially damage the housing or the feed. Luckily it all came together nicely, and I suspect over time as I take them out a bit more, it will become a little easier.
Final Score and Conclusion
While I am already curious about what other pens I can fit this Platinum nib into, I think I will let it stay inside this Vac Ultem for now. Despite the downsides I mentioned in the Part 1, there are some aspects of this pen I do like, and they do compliment this gold Platinum nib, mainly the vacuum filling system and more comfortable grip section. If I had given the overall pen, a 5 out of 10, now with that Japanese broad nib, it becomes a 7 for me.
Friday, August 29, 2025
Gravitas Ultemvac but with Platinum 3776 Century Nib
Introduction
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| The Gravitas Ultemvac with the Platinum 3776 Century Broad nib installed by the time of writing |
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| The Platinum 3776 Century Broad Nib |
Thus, I began looking for a way to see if I can put this lovely broad nib in another pen, after finding out I can actually pull it out without break anything. Then I remember about the Gravitas Ultemvac, or Vac Ultem as I prefer to call it, really. I remember YouTube reviews from about a year ago, and the information that it is Jowo-threaded.
A vacuum filler in this interesting plastic material and can take on any nib units as long as it is Jowo-threaded? I had to try, and jumped at the opportunity when Pen Venture had a discount sale for it. But there was a potential issue, I came to realize Platinum nib and feeds are friction-fitted, and it doesn’t seem to have an unscrew-able housing unit. I don’t believe I can just fit them in any Jowo housing unit, and found nothing online that says it is possible.
I figured I could try my chances by simply taking the nib only and fit it onto the Vac Ultem’s default feed. Fortunately, I found a custom housing for both the Platinum nib and feed from Flexible Nib Factory. I ordered the Jowo threaded unit, as a well as one with a Bock threads, just in case.
While I would like to get immediately into putting the Platinum nib into Vac Ultem, I believe I should at least give an idea about the pen itself with a personal review.
Gravitas Vac Ultem Review
I got the Vac Ultem first, and of course I had to try it. While I would go through the shape of the pen like a lot of different reviews, but I am going to leave a few pictures of the pen to give a good look at its shape and appearance.
First of, it is a vacuum filler, as stated earlier or one can guess from the pictures. It is made of Ultem, a different kind of resin that apparently, according to Gravitas’ own words on their website, “offers exceptional strength, stiffness, and chemical resistance”. It sounds intriguing, because they also mentioned this kind of material is used in aircraft. Although I do wonder which part specifically they are referring to. If it really does what Gravitas said, I suppose this Vac Ultem is likely a tough piece, of a fountain pen.
It is also a clipless design, which is seems to be a Gravitas design language, and while Jowo threaded, I do not recognize the nib or feed. The nib does have the Gravitas logo laser-engraved, and Gravitas, on the pen’s own page, stated it is a #6 nib and manufactured by themselves. The feed is made out of ABS plastic. I ordered the nib in medium, which is always reliable when I am not sure what size to really get.
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| The grip section. |
The grip section is of decent length and starts out, from where it meets the body, straight and flat before quickly tampers down a little before it flared out at the end. This creates a notable concave shape near the nib, where I can grip it comfortably, and rest on that little flare. But I can also rest my fingers on the flat area at the back, if I want a slightly larger grip. Either way, the grip section is comfortable, even for long writing.
It has this metal piece that is titanium, around the area where the pen body meets the grip section. I believe it is meant to reinforce the area, since that is where the plunger snaps forward after being release of tension. Additionally, the vacuum nob at the back where the blind cap screws and unscrews is also made out of titanium.
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| That forward ink reservoir |
One interesting feature of this Vac Ultem is this forward reservoir of sorts, located between the nib unit and the reservoir that is the body of the pen. What I can guess from this feature is that it can help serve a source of ink for the nib and feed when the blind cap is screwed and the plunger shuts off the rest of the ink supply from the nib. This is a common procedure for vacuum fillers; I will have to unscrew the vacuum nob to allow ink to flow to the nib. This little forward reservoir eliminates the nib to do that, and thus I can go straight into writing with the pen. I only will need to unscrew the nob when the reservoir is dried out.
It is a nice feature, and I actually do like I don’t need to unscrew the blind cap to writing for a longer period of time. And if I need to prevent potential ink leaks, say during a flight, I just unscrew the vacuum nob, thus pulling the piston back a little and shake the pen to let the ink back into the main reservoir before screwing the cap, thus shutting off the ink supply for a clean flight.
Finally, the nib itself, but I just going to be blunt; it is a mediocre nib. I inked up the pen with Waterman Serenity Blue, and while the ink always flow, never hard start or dry up, the writing experience leaves much to be desired. It feels like dry for my taste, and while decently smooth, with a touch of feedback, it was only a rather unremarkable kind. To be clear, it was not scratchy, just boring, nothing sensational. It will only serve its intended purpose.
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| The default Gravitas nib that comes with the pen |
Pros of this Fountain Pens
Overall, the pen has its pros; First, a comfortable grip section that is just the right size and shape to accommodates different grips. Secondly, a large ink capacity being a vacuum filler. Thirdly, it is well-built with these metal parts and the ultem material. If the materials are what they describe they are, this will be a durable pen. Plus, despite the metal parts, the Vac Ultem is still light in my hands.
Fourthly, a nice addition of the forward ink reservoir for writing without needing to unscrew the back knob. Fifthly, the grip section with the nib can be unscrewed, making it easy to clean and maintained. Apparently the vacuum knob can disassemble as well. There are some flat sides where I can rest this Asvine disassembling tool, which fits perfectly coincidently. While I wouldn’t always do this, it is nice to be able to do so, when I need a more thorough cleaning.
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| An Asvine wrench is able to fit onto that knob. |
Finally, the fact it is Jowo-threaded means I can change out the nib unit to anything I fancy as long as it is compatible. Very nice.
Cons of this Fountain Pen
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| Plastic threads on metal threads |
However, the pen have some notable cons; firstly, plastic on metal. The cap threads meets the metal threads on that titanium reinforced part. The same can be said for the plastic cap, and vacuum knob at the back. I don’t know how well threads on Ultem can handle the stress from metal threads, but I should look out for them, which is why I put some scot-tape on the treads at the back to reduce any friction between the threads. I did not do the same for the threads between the cap and body because I personally think it would look weird.
Secondly, the nib. I already say my piece, but it is not really enjoyable. It only just works as a concept of a nib. I tried opening the tines a little to see if it improves the wetness. While it did, it was only a little and there was not much improvement to overall performance.
Thirdly, and most surprising to me really, is the threads between the cap and body. I believe other reviews mentioned this, but for some reason, these threads have the potential to snag or catch each other when I tried to screw the cap back on. From my experiences so far, it seems to be a specific spot, because otherwise, the cap would screw on like normal. But there are times the threads would catch upon first contact and I suddenly can’t screw the cap any further without potentially damage the threads on it. Thus, I have to unscrew and find a good spot for the threads to meet and intersect and allow the cap to screw onto the pen again.
I never experience something like this on a pen before. At worst, one of my cheaper Chinese pens would have less than smooth threads when screwing on the cap, but none of them would outright get stuck when both threads meet. I heard a similar complaint from Doodlebud’s video, which came out months ago. So I wondered if Gravitas heard about this because months later, and I also got a similar issue, it might look like it has not been resolved.
Fourth con and more personal complaint, I did state this pen post really deeply and securely. So it should be a good writing experience posted, right? Unfortunately, I tried and still did not like it. The cap does weight like nothing, and it goes down deeply onto the back of the pen. Yet I think the issue is that its balance is still not good enough because it is still a touch too long for my hands. For quick notes, it is no problem. For longer writing sessions, I quickly come to notice the pen did not stay comfortable in my hands any more. Quite unfortunate, because it looked like such a good posting fountain pen.
Conclusion
After some consideration, I think I would personally give something like a 5 out of ten. I have good things to say about this pen, but I think it is also held back from being an amazing pen. It is a new and exciting pen from a younger brand, at the end of the day, and I think it works, just that I wouldn’t always reach out for if I want something to write with.
In fact, the performance of the nib finally made me quit testing the pen after a week. I just emptied it and stored it away until that custom housing for the Platinum nib finally arrives, although I did give the nib another shot and this time, I used a different ink. I will cover this briefly in the part two of this Gravitas Ultemvac with Platinum nib review.
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