Saturday, August 6, 2011

Review: Uni-ball Signo RT (UM-138) 0.38 mm Gel Ink Pen

This is a review of the Uni-ball Signo RT (UM-138) 0.38 mm Gel Ink Pen in blue-black and lavender purple-black. Not surprisingly, these pens were also acquired from JetPens!

- Water-based pigment gel ink
- Steel point
- Rubber grip

The Body

The Uni-ball Signo RT (UM-138) line, like the DX UM-151 line, have a good-sized barrel for those who don’t like thin barrels that often accompany micro tips. It’s very comfortable to hold and didn’t strain my hand after extensive writing.

If you’ve read my review of the Uni-ball Signo DX (UM-151) 0.38 mm gel ink pen - essentially the non-retractable version of this one - you’ll know I was disappointed that the grip was so small. There’s a gap between the grip and the metal tip, leaving plastic barrel which is where my fingers are usually gripping!
Top to bottom: Uni-ball Signo RT 0.38 mm in lavender purple-black and blue-black, Uni-ball Signo DX 0.38 mm in blue.
Size comparison, uncapped and nibs out.

Hooray for this pen! The grip actually extends all the way to the metal, giving me the perfect grip. I usually prefer non retractable pens because for me, they are more comfortably weighted when the cap is on the back - a small amount of weight that obviously lacks in a retractable. But in this case, the grip overrides the weight when I have a lot of writing to do.

As for the nib and ink, because this pen is the same as the DX UM-151, only in the retractable form, I won’t blabber on about my impressions - they really didn’t change. The nib still feels solid, the ink is still a nice (dark) color.

From my review of the DX UM-151:

The Nib

Despite being a fairly thin tip at 0.38 mm, comparable to the 0.3mm Pilot Hi-Tec C, I didn’t have a problem with the writing. Ink flow was very smooth and, perhaps because I’m used to writing with fine nibs, I did not feel the nib was scratchy. I have a friend who tried it, and she commented it was a bit scratchy for her - but then she usually writes with 0.7 mm nibs and larger.

The nib is also well built. As usual, I performed my highly advanced scientific test of nib strength by violently tapping the nib on my notebook (in this case, I have stuck with my trusty Quo Vadis Habana). The nib held up well to my abuse and again, I suggest you don’t try my HASTONS (highly advanced scientific test of nib strength) at home. Unless you’re prepared to lose a pen or two. Even with heavy writing, the nib held up well. I did not have any problems with ink blobbing on the ends, which results in ink blobs - often a problem with cheaper pens. Personally, though I love the Pilot Hi-Tec C line, I think the 0.38 mm nib feels sturdier than Pilot’s 0.3 mm, or even the 0.4 mm nib.

The Ink

It’s hard to drool over thick, bold lines of ink when your nib is only 0.38 mm. But from the color of the ink through the barrel, it’s pretty nice. And the tiny little 0.38 mm lines left by the pen are pretty nice looking, too. The blue, blue-black, and bordeaux-black** that I tried out are all very nice but obviously are not brilliant, happy colors. They are quite professional looking though.

So far, the ink is lasting me quite awhile. The ink cartridge is quite wide and because the nib is so thin, it doesn’t use up ink very quickly. This is great for those of us who want a pen that lasts a long time. Not so great for those who have OCD and obsessively monitor their ink levels as they write with excitement so they can proudly use a pen from start to finish without their ADD taking over (not me).

**NOTE: in this review, I had the blue-black and the lavender purple-black.


Fortunately, these pens are refillable. However, like most refillable gel ink pens, the refills only come in select colors. Unless you’re really into black, blue, blue-black, and red, you’re out of luck. Hopefully Uni-ball will add some more colors to their available refills.


JetPens - $1.65
JetPens Refills - $1.35


I really like the Uni-ball Signo DX line. It’s a great pen for anyone who is curious about the micro tip pen world but are hesitant to try a softer nib in fears of breaking it. The pen is really nice looking and the retractable with extended grip is even more comfortable than its non-retractable counterpart. Great for fine details in doodles and writing. I still can’t believe it’s only $1.65!


Anonymous said...

Strange as it may sound, I have many of the Uni-ball Signo DX (UM-151) 0.38 mm and have not liked the grip either. But I was unable to pin point my dislike for it. Sounds crazy but it is true. I always am holding the plastic between the grip and the pen. I guess I love the ink and the colors of almost all of the ink that I end up not paying to much attention to the problem of the grip. I usually don't like retractable pens but I am going to give these a shot. Thanks-

GourmetPens said...

I hear that! I really do love the ink and they write so nicely and sharply. Maybe Uni-ball will hear my pleas and fix up the grip on the UM-151 hehe

Anonymous said...

Thanks for posting this review. I wasn't sure if there were any differences between the Uni-ball RTs and DX (UM-151s) until I read this.

Ironically, even though it's cheap at $1.65 in the States, it's even cheaper in Taiwan, where my friend says they retail for about $0.35 each (all colors!). (I'm making her get me a box of them next time she gets the chance.)

GourmetPens said...

:| $0.35?!?! OMG! That is so awesome.

I'm glad the review was useful to you :)

Romann Booth said...

Worst pen I every bought the, the ink keep leaking on my fingers and ruining my work.

Azizah Asgarali said...

Really?? That's so unusual.. Even in the 0.38mm?? I would imagine you just got a dud.. I have many of these and haven't had anything like that happen.. you should contact Uni-ball. I bet they'd replace them for you :)

Yuri Boyka said...

Ive written with thin tips before, but the combination of liquid/water-based ink and .38 makes it very scratch. Id love me something this thin, but with gel ink. Does that exist Azizah?
I think the gel ink, would make it flow better, but maybe at the cost of color darkness and ink distirbution.
I use the pen mostly for writing numbers(physics, math, chemistry)

Azizah Asgarali said...

Hey there! Off the top of my head, I can think of the Zebra Surari that has non water-based gel ink but it's smallest tip size is 0.5mm -

But there's also the Uni-ball Style Fit, available in 028mm, 0.38mm, and 0.5mm! That might be your best bet :)

Leigha7 said...

There's a 0.38 Pilot G2, which is available pretty much anywhere that sells pens. I'm not sure how it compares to other pens of that size because it's the only one I've ever actually seen in a store, and thus the only one I've used. (That's actually why I came here, to see how others compared.)

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