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!

Features:

- 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 left to right: Uni-ball Signo RT 0.38 mm in blue black, Uni-ball Signo RT 0.38 mm in lavender purple-black, Zebra Sarasa Retractable 0.7 mm in indigo blue, Pentel Slicci 0.7 mm in red, Pilot Hi-Tec C 0.5 mm in cutie grape, Pilot Hi-Tec C 0.4 mm in hunter green, Pilot Hi-Tec C 0.3 mm in mauve.

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.

Eco-Conscious?

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.

Price:

JetPens - $1.65
JetPens Refills - $1.35

Overall:

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!