I will spare you the story behind the TWSBI brand and the Diamond 530 but if you haven't heard already, go to FountainPenNetwork (FPN) and search for "twsbi". Essentially the brand was started by a Taiwanese gentlemen (these pens are made in Taiwan) and the Diamond 530 was created with a lot of input from the FPN community. This makes it a community project and I can see how a lot of careful thought went into its creation.
As a side note, if you're wondering how "TWSBI" is pronounced, the general consensus is "twisbee" or "twizbee".
There aren't many places where you can buy TWSBI pens. There are actually at least 2 more pens in the brand, besides the Diamond 530: a mechanical pencil and another, more expensive, fountain pen. The best place to snag one is on eBay, directly from the producer. What makes this a very sweet deal is the fact that the shipping is very low. The pen itself is $39.99 while the shipping is only $3.39.
My TWSBI is a clear demonstrator but you can buy colored demonstrators as well. The next version of this pen has been under development for a while and I believe it will be called the Diamond 550. While the 5xx generation has a piston-fill mechanism, there's also a future Diamond 700 (if I'm not mistaken) which will be a vacuum-filler.
I hesitated a long time to buy this fountain pen, not because I doubted its qualities but because I wasn't sure what nib size to get. At the time, there were 3 sizes available: M, F and EF. Finally, I settled on EF and it turns out I made the right choice. This nib is close to perfect, at least in my non-expert opinion. At present, B nibs have also become available and you can even buy the nib unit separately if you so choose. It's about $20 on eBay. The nib unit is made up of the section, the feed and the nib itself. You can just screw it on your TWSBI after unscrewing the original section. This allows you to change the pen's characteristics and writing qualities on the fly.
The modularity and serviceability of the TWSBI Diamond 530 is a big part of its appeal and a major feature of this fountain pen. Firstly, the pen was designed to be completely disassembled for servicing, and anyone can do it easily. Here's a great video from TWSBI's creator, showing how to disassemble the Diamond 530 and then put it back again:
Secondly, the pen comes with printed instructions of how to service it yourself, along with some silicone grease and a small wrench like the one you see in the video.
The instructions, grease and wrench, along with the pen itself come in a nice acrylic display case which, although plastic, looks very high quality. I suspect part of the appeal lies in the edgy industrial design and the precisely machined parts. The plastic box, in turn, comes in a thick cardboard box with the red TWSBI logo on the lid. Very classy packaging and I challenge you to show me another $40 fountain pen which comes with such impressive packaging.
So what kind of fountain pen is the TWSBI Diamond 530? It is a premium-looking pen, fairly large in size, with a modern, industrial design. People compare it to a Pelikan M800 and even though I haven't held a Pelikan in my life, that's how I imagine it would feel. The Diamond is very well built, and you can tell by its heft. The body isn't smooth like a normal pen but rather faceted, similar to a cut gemstone. While some people dislike this feature, I absolutely love it, not only because it make the pen look just like its namesake, the diamond, but it also prevents it from rolling off the desk.
The cap is another very solid affair and all the shiny bits are actual metal. This pen feels so sturdy that sometimes I imagine it is made of glass. The cap is a twist-on affair, the way a proper cap should be (in my humble opinion). This feature is sadly shadowed by a little annoyance, namely the fact that the cap is rather tight when screwing and unscrewing. This could be due to the tight tolerances of the machining process and many people have mentioned it. The cap does loosen up a bit after using the pen for a few weeks but it is still not at the level I'd like it to be. You could try applying a little silicone grease to the threads and that will certainly help but it does make the pen sticky and it will get on your fingers.
In the end, the tightness of the cap is only a problem if you want to make it one. It doesn't bother me that much but it is a minor blemish in what could be the perfect fountain pen.
The clip is sturdy and a bit stiff but that only means that it will grab hold of anything you clip it on and won't let go easily.
The cap is topped off by TWSBI's logo which I like, though some folks might find it garish. I think it gives the pen a certain flair and adds some color to the transparent body.
At the other end we have the knob for the piston. This knob is another point of contention for certain folks because it is not protected and when the cap is posted, it rests directly on the knob. If you are not careful when un-posting the cap, you might twist the knob, thus squirting ink all over. To me, this seems like an extreme scenario for several reasons. First, I never post the cap (I'll tell you why in a minute). Second, the knob seems to be tight enough to prevent casual twisting. Third, if you do twist the knob you will learn not to do it the next time :)
The knob issue is, thus, the second flaw of the TWSBI Diamond 530 and a big one for some people. For me it is a non-issue. The tightness of the cap is of much greater concern to be than the knob and that's simply because I don't feel the slightest need to post the cap. Why? Because the cap is heavy and it messes up the balance of the pen were it posted. The pen itself is thick, long and heavy enough to not require posting. Then again, there are those who can't bear writing without posting the cap and in that case there's nothing I can say that will make them love the Diamond 530.
Moving on, the piston mechanism guarantees a larger ink capacity than your standard converter, such as the one Lamy uses. There's still a lot of space wasted by it, but this will be improved in the future Diamond 550 by a redesigned mechanism which will increase capacity by about 30%. The capacity of the Diamond 530 is another non-issue for me because the ink still lasts a long time, at my rate of writing.
One thing I usually dislike about piston fillers is that they can be hard to clean inside. Sure, you can flush them by pumping the piston two dozen times but it would be nicer to get inside the pen. The TWSBI Diamond 530 makes this easy by allowing you to unscrew the section from the body. I did mention earlier that it can be fully disassembled, right? Not only that but you can go crazy and remove the nib and feed from the section and you can also take the piston mechanism apart.
I haven't had the chance to disassemble the Diamond 530 for the simple reason that the fountain pen came perfectly calibrated right out of the box, so there was nothing to adjust. Since I'm using the same ink in it, I've had no need to take it apart for cleaning. Speaking of ink, the TWSBI Diamond 530 is dedicated to Noodler's Polar Brown which I've reviewed previously.
Moving back to the piston, you should probably know that there were several versions of it on the market. My version is known as version 1.5 and it is an improvement over the original which sometimes and under certain conditions leaked a bit from the first seal (there are two seals in the piston). Speedy, TWSBI's creator, has always been incredibly supportive of anyone who has experienced issues with the piston (or anything else for that matter) and has promptly shipped the updated piston free of charge. Such customer service is hard to find these days and it only makes me more confident in my future TWSBI purchases.
If you were to buy one of these pens now, chances are you will end up with a piston version 1.6 or even 1.7. I've kind of lost count of the different versions floating around but the point is that the pen is constantly evolving and improving.
One of the best things about the TWSBI Diamond 530 is the writing experience. Though I was a bit fearful of the EF nib, in the end it proved the correct choice. Thankfully, it is not a Japanese EF, but rather a European one. In fact the nib is made by Schmidt in Germany.
The nib is nicely engraved with the TWSBI logo along with some flourishes. There's also a tiny "EF" engraved on the side. Those who are hoping for flex will be disappointed but the nib was never advertised as having flex. Personally I find it hard as a nail but some people have reported a little bit of flex to it. If a nib is not explicitly a flex, I will always be careful not to force it in any way for fear of springing it.
A few people have also reported minor issues with their nibs, in the form of scratchiness or poor ink flow. It may be that these nibs are not entirely consistent. After all, what can you expect in such an inexpensive pen? From what I've been reading, the vast majority of TWSBI owners are very happy, even ecstatic, with their fountain pen.
Thankfully, I haven't had the slightest problem with my Diamond 530. I haven't had to adjust it in the slightest, and it worked right out of the box. It wrote beautifully from the beginning and my impression is that, with time, the nib has become even smoother. Now, it is buttery smooth and I can't wait to pop off the cap and write or draw something with it. Compared to it, the Pilot Prera, which I previously considered to be a very smooth, feels like a dry writer.
Noodler's Polar Brown ink works wonderfully in the TWSBI Diamond 530. Not only does the brown liquid give the transparent body a distinguished look but it also stains the nib slightly and gives it a golden tint. As for flow, it is perfect. Overall I'd say the pen writes on the wet side but not too wet.
Another great feature of the TWSBI is that this pen starts immediately, no matter how I store it, no matter for how long. It is always eager to write.
Here are some of the sizes I have measured, for those interested in such details.
Length capped: 14cm / 5.5in
Length un-capped: 12.8cm / 5in
Length of cap: 6cm / 2.36in
Length posted: 17.6cm / 6.9in
If raw sizes don't mean anything to you, here's a side-by-side comparison of the TWSBI Diamond 530 with Noodler's piston filler, Pilot Prera and Lamy AL-Star. As you can see, the TWSBI is just a tad longer than the Lamy, both capped and uncapped, but it is definitely heavier and feels more solid to hold. In comparison, the Prera is the shortest pen in the lineup, while the piston filler from Noodler's is the thinnest. Here's some more food for thought: the Pilot, Lamy and TWSBI all have a comparable price. They each have their strengths and weaknesses but overall I prefer the TWSBI.
If this review has convinced you to buy a TWSBI, I would suggest to do it now. The next, improved, version will cost an extra $10 due to rising material costs. Although the successor will have some improvements such as extra ink capacity, the reality is that future TWSBIs will cost more than the Diamond 530.
I am already contemplating to buy the vacuum filler when it becomes available. This brand has a great future as long as development and customer support continue as they have until now.
To conclude, the TWSBI Diamond 530 is probably the best fountain pen you can find at $40, or even below $100. It is not perfect and the piston knob issue might irritate some folks enough to pass on this pen. The tightness of the cap is my only dislike of the pen but I can live with it. I believe that the positives far outweigh the negatives. Finally, a poor fountain pen lover can afford something which feels and writes like a much more expensive instrument but at a fraction of the cost.
The writing samples below are the same ones I used in my review of Noodler's Polar Brown.