Review by Tina Koyama
My vast love of colored pencils is directly proportional to my frustration with sharpening them. While my desktop Carl Angel-5 does a decent (and sometimes very good) job on most colored pencils of average barrel diameter, it can’t handle pencils of slightly larger girth, which happens to be the case for two of my favorite colored pencil lines – Derwent Drawing Pencils and Caran d’Ache Museum Aquarelles. (While I don’t use them often, I would think jumbo graphite pencils would run into the same issue.)
When I’m home, I often hand-sharpen them with a knife, but as an urban sketcher, I often need to sharpen in the field. I can’t take a knife on a plane, and it seems imprudent to stand on a street corner with a knife in my hand. So I’m left with portable sharpeners as my primary option.
I’ve tried many with terrible to fair results; none have been excellent. Ever hopeful that the grail is still out there, I decided to try four that seemed promising:
- Sonic Ratchetta with Notification
- Kutsuwa Stad T’Gaal
- Kum No. 410 Magnesium 2 Hole
- Kum Special Diameter Pencil Sharpener for Triangular & Hexagonal Body Pencils

Sonic Ratchetta
Of the four, this see-through, brightly colored, high-tech-looking gizmo “with notification” intrigued me the most. It took me a while to get the hang of the ratcheting motion, but once I did, I realized it could save wear and tear on my hand and wrist, which I appreciate. The sharpening blades turn as you sharpen, requiring only a short back-and-forth motion, so you don’t have to crank your wrist all the way around and continually regrip the pencil.
The “notification” feature – a button that pops out when the pencil is fully sharpened – doesn’t seem to work consistently. However, I get a nice sharp point on my standard-diameter pencils, both colored and graphite. Unfortunately, neither of my two thick pencils – the round-barreled Derwents and the semi-hexagonal Caran d’Aches – would fit. To be fair, the Ratchetta’s description says nothing about accommodating fat pencils, but I guess I got so excited about the design that I forgot about my objective.
Kutsuwa Stad T’Gaal
This one gets the prize for the most puzzling name. And once again I’m guilty of getting so excited about the design that I didn’t read the description carefully. When I saw the dial that enables choosing among five settings, I must have jumped to the conclusion that the settings were related to pencil diameter. (I think I was imagining the wall-mounted classroom sharpeners of my youth that had a variety of hole sizes on the dial.)
Reading the instructions that came with the Stad T’Gaal (and by “reading,” I mean looking at the diagrams, since I can’t actually read Japanese), I quickly realized that, in fact, the settings numbered 1 – 5 are not about pencil girth at all but instead enable you to choose the length of the sharpened core. Setting 1 results in the shallowest cone; setting 5 the steepest.
Chagrined at my misinterpretation, I was nonetheless rewarded – both the Derwent and Caran d’Ache pencils fit! Well, perhaps “fit” is too charitable. It’s more like I am able to maneuver them in with some effort, like squeezing into jeans from a few years ago. And like those jeans, there is an unseemly consequence: the mouth of the sharpener takes some of the finish off those thicker pencils. Nonetheless, the Stad T’Gaal does a clean job of sharpening them at various core lengths. Standard-size pencils come out beautifully, too. The steepest No. 5 setting is probably not long enough to satisfy fans of “long point” graphite sharpeners, but it exposes an impressive length on my thick-core Derwents. Bonus points for coming in several fun colors.
Kum No. 410 Magnesium 2 Hole
This no-frills sharpener is the least appealing of the four I tried because it doesn’t contain the shavings. Away from home, I must remember to catch the shavings in a tissue until I’m near a trash can, which isn’t a huge deal, but is still something to think about.
Equipped with two holes, the smaller is intended for standard-diameter pencils, and the larger accommodates pencil barrels up to 10.5mm. Paradoxically, neither of my thick pencils sharpens well in the larger hole – the blade doesn’t seem to make contact evenly – but using the counter-intuitive smaller hole, both the Derwent and the Caran d’Ache are sharpened satisfactorily. It exposes a decent length of core without coming to a deadly point (which some graphite writers covet but isn’t really necessary for colored pencils). The mechanism is not what I would call stellar, as I have to exert extra effort or pressure to get the job done, and it doesn’t feel secure.
As I was sharpening with the smaller hole, the sensation and result gave me déjà vu, and then I realized that the Kum No. 410 is probably identical to the inner workings of the dome-covered Kum 301.08.21, which is my current sharpener of choice that I was hoping to improve on. (Of the two, I like the domed one better, since it contains my shavings.)
Kum Special Diameter Pencil Sharpener for Triangular & Hexagonal Body Pencils
I had the highest hopes for this Kum because its name indicates that it’s intended for pencils of special diameter. Surely my difficult-to-accommodate Derwent and Caran d’Ache qualify as “special”! Like the Kum No. 410, this one offers two holes that look suspiciously similar to the ones in the 410. (Don’t tell me I’m having yet another case of déjà vu!) But in fact, they are not identical because neither hole accommodates the Caran d’Ache. The smaller of the two holes does sharpen the Derwent adequately.
Incidentally, although I don’t use them much, I was curious whether a couple of Koh-i-Noor jumbo triangular pencils – a Triograph and a Magic – would fit. Nope.
Final Impressions
Since it’s the first portable sharpener I’ve found that can accommodate all the pencils I typically use and also sharpens beautifully, the Kutsuwa Stad T’Gaal is a versatile keeper in my bag. If only its mouth were just a tiny bit wider, it wouldn’t scrape the lovely matte-finish lacquer on my pricey Caran D’Ache Museum pencils. The grail search continues.
Tina Koyama is an urban sketcher in Seattle. Her blog is Fueled by Clouds & Coffee, and you can follow her on Instagram as Miatagrrl.
DISCLAIMER: The items included in this review were provided free of charge by JetPens for the purpose of review. Please see the About page for more details.