pen review: twsbi diamond 540
Tuesday, November 1, 2011 at 10:00AM 
Many excellent things have been written about the TWSBI Diamond 530. A clear, piston-fill, steel-nib demonstrator available for US$40, it was one of the best pens in its price range. It was also constructed to be completely user-serviceable -- it came with instructions on disassembly and reassembly, along with a tub of silicone grease and a purpose-built wrench for removing the piston.
I used my 530 extensively - it was a workhorse of a pen that I could have easily held onto for years. That is, until TWSBI came out with its successor, the Diamond 540. Despite being a well engineered pen that featured a great design, the 530 had two minor issues that kept it from being a classic: the threading on the cap was very tight -- enough so that to remove and replace the cap took more effort than one would expect; the piston was likewise stiff, and would occasionally stick -- I would worry that I was going to damage the mechanism when filling it with ink.
I'm pleased to report that the 540 fixes both of those problems. The cap still feels secure on the pen, but it now twists on and off with ease. The piston was also fixed. Now it moves through its entire range of motion without issue. Additionally, they've increased the ink capacity of the pen to a notable degree. The pen almost holds a full 2 ml at capacity.
The steel EF nib is the same one that shipped with the 530 -- in fact, the nib units are interchangeable and available from TWSBI separately. It's a stiff nail, so there is neither flex nor spring, but it does write smoothly and reliably. It's an easy starter, and can take being uncapped for a few minutes without much issue.
While the price has gone up by $10 over the 530, it is still an excellent value at this price point. The only improvements I could suggest now would be a spring-loaded clip and the option for a gold nib - both things I would only expect on a pen costing twice as much.
I can't recommend the Diamond 540 enough. It's one of the best values for its price, and nearly rivals pens costing more than twice as much.
The TWSBI Diamond 540 is available from:
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Reader Comments (5)
Thanks for the review! Trying to decide if I really want one of these, or if I should save the $ and add some to get a Pelican M205 or Pilot Vanishing Point.
As always, enjoy your reviews.
Here's my http://peninkcillin.blogspot.com/2011/04/twsbi-diamond-530-fountain-pen-review.html" rel="nofollow">review of the TWSBI Diamond 530. These are awesome pens. I'm especially glad I got the 530 for $40 as the 540 is "more" expensive at $50. To be honest, though I appreciate the extra capacity, it isn't worth an additional $10 to me. I don't write so much anyway.
The tightness of the cap can be resolved quite easily actually. There's a http://www.amazon.com/Novus-Plastic-Polish-Scratch-Remover/dp/B001J7EVCQ/ref=sr_1_1?ie=UTF8&qid=1320197433&sr=8-1" rel="nofollow">scratch remover kit on Amazon that works wonders. I read about it on FPN. Smear the #2 paste on the thread, screw the cap on and off a few times, wash it off, then use the softest compound (#1) the same way. Tightness gone.
Yes, I know that the kit is $14 but I see it as a long-term investment in a tool, not a one-time expense, considering I can use it on other pens as well as other plastic doodads.
Good review, I was planning on doing one myself... and the ROC 100 too
The 540 is really an awesome pen, well worth the price for what you get. The new color demos are awesome, too! I just saw them yesterday for the first time, and they live up to my expectations. I appreciate your link to my store too, Dave!
After reading several reviews on different sites about this pen I ordered one from Amazon with an EF nib. I'm very impressed withe fit and finish. The ink capacity is great. This pen writes flawlessly right out of the box; no dry starts, skipping or scratchiness. (Surprising for an EF nib)
I collect and restore vintage Sheaffer Balance levers, Touchdowns and Snorkels, along with Parker Vacumatics. This pen will keep up with the best of them at an affordable price. I would recommend this pen as a first foray into fountains or a daily writer. It appears durable and dependable, time will tell!