Review: uni-ball Power Tank (original capped model)

The uni-ball Power Tank is a mass-market take on the famous Fisher Space Pen‘s pressurized ink technology. The special ink can write in extreme heat and cold, underwater, or in the vacuum of space. I don’t really need it to do all those things, but it’s a comfort to know how reliable the pen can be.

This original model was my favorite go-to pen during high school. Since that time, the original capped version has been retired in favor of a retractable model (and more recently the Smart Series). While the pen’s legacy lives on, the newer iterations pale in comparison to the original. Not only does the classic blue Power Tank look fantastic, but it also writes more smoothly than any ballpoint I’ve ever used.

I still have a couple ink refills and one barrel, but I’m writing with a dinosaur. Not even Brad Dowdy, the Pen Addict himself, knows where to pick this pen up anymore. JetPens doesn’t stock it, and uni-ball’s U.S. website doesn’t even acknowledge the existence of the Power Tank line. Of course the world moves on from any product, but it’s a pity that the new models neither look nor write as well as the old one.

When I originally bought the Power Tank, it came in three-packs at OfficeMax (black, blue, and red). The blue was always the standout, and later I found it sold singly in such mainstream locations as Walgreens. Once it was even paired with a stick of gum for some promotion. Not exactly where one expects to find a top-notch writing instrument. By 2007 they were hard to find, and I picked up my last two at a bookstore.

The Power Tank has a very small cap, which means its balance is barely affected by posting. Meaning you can either set the cap aside or post it without feeling like you’re using the pen “the wrong way.” The tapered shape nestles nicely in the hand, and the wide grip is just rubbery enough to grasp without feeling too squishy.

I always appreciated the little window in the cap. It’s utterly unnecessary of course, but a cool touch.

The barrel has a reflective label set under the surface which reads “Pressurized Refill – 3000hPa” That’s equivalent to 43.5 psi. I’ve no idea how that compares to the Fisher Space Pen’s internals or the modern Power Tanks.

As far as I know, the original Power Tank was only sold in the 1.0 mm variety in the U.S. The modern RT and Smart Series are available in .7 as well. That might seem pretty thick, especially compared to many foreign pens, but the 1.0 mm is actually thinner than your everyday American ballpoint. Here I’ve compared it to my two other pressurized ink pens – you can see that Fisher’s “fine” tip is identical to uni-ball’s widest size.

Notice the ink consistency (click the image for a larger view). The old Power Tank – virtually unused for 5 years – writes better than the Fisher, which I use every day. (It has been dropped a few times on its nose, so that might have something to do with its poor performance.) The Smart Series High Grade started off very faint – I actually had to draw the first line twice to get much of anything down on the paper. It never felt as smooth as the older model, even after it warmed up. Maybe it’s just nostalgia, but I’m left feeling that uni-ball is slacking a bit on the Smart Series.

The one downside to the Power Tank is its relatively fragile body. The eye-catching translucent plastic is prone to cracking, and the grip wears down easily. Indeed, my current barrel has a strange crack near the end, despite sitting in a drawer for years. I’ve also snapped off the clip when using it on a jean pocket. So in the end, the Power Tank really isn’t suited for an everyday carry, especially when I can’t find any more to replace it.

Of course, feel free to get in touch if you know where to pick some up!

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