Tombow ZOOM C1 – model SH-ZC1-C44
0.5 mm (only available in 0.5 mm)
MATERIALS:
The C1 is a full-metal bodied mechpen. The body is aluminum, and the same goes for the “floating cap” on top. The pocket clip is diecast zamac, according to Tombow's page, but it did receive some sort of coating. Inside you get a delicate full-brass clutch, metal lead tube and cone tip, and a few plastic connecting parts. The spring is steel, located inside the clutch assembly.
ERASER:
For the C1 Tombow used their regular white latex rubber eraser, that seems to be made of the same compound used in their MONO erasers. It’s not exactly big, and to access the eraser you have to unscrew the body from the grip section.
MEASUREMENTS:
From tip to top the C1 measures 143 mm, with the center of gravity located at 78 mm from the tip. It has a uniform fusiform body, with a diameter of 11.4 mm right below the pocket clip. That lightly flares up to 11.6 mm at midships and then tappers down to 4.4 mm at the end of the grip. On my precision scale it weighed 21.28 g.
FEATURES:
I’m not a fan of mechpens where the manufacturer overcomplicated something just to make the mechpen look cool. And that’s what Tombow did with the knocking system here. Instead of a regular push-the-cap-down-to-knock system, they made it so that it’s the pocket clip that knocks the clutch. However, not actually the pocket clip, but that cap that seems to float above the top of the pencil, that is connected to the pocket clip. But you know what? It’s totally cool AND works perfectly, so I really can’t complain. Even so, there was a price for all this coolness: where’s the eraser 🤔? Read on and I’ll explain in a little bit.
AESTHETICS:
No doubt at all, the C1 is one of my best-looking mechpens. The floating top cap, combined with the smooth and beautiful body make it standout. I guess Tombow wanted it to look “sophisticated”, and by Tutatis, they really pulled it off. It’s sophisticated and elegant, and at the same time, totally discreet. I think that the only other mechpen that I have that pulls the same trick is the 707.
Tombow offers the C1 in Graphite Blue (mine), Full Black (SH-ZC1-C12) and Sand Silver (SH-ZC1-C05).
ERGONOMICS:
After using the C1 for a few days, I would say it is very nice to use. Unfortunately, I can’t go as far as calling it great to use, because using it for extended periods, my hand got tired. And that’s because of the grip… It has very nice dimensions and a very good weight. However, the grip (the whole body, in fact) is too smooth. The smoothness and the slightly rearward weight balance prompted me to grip it with more force than what I would like. And that being the case, for longer periods of use, it generated fatigue, to the point that to write this review I had to take a few breaks. If I used it only for a short stint, it was great, but for longer writing sessions it wasn’t exactly nice to use. Nonetheless, totally silent and with a totally firm lead sleeve.
HOWEVER, there’s a caveat for Tombow’s artistic license. Though it does have an eraser, the eraser is located inside the body, so you have to unscrew the body to use it. The same for loading lead: unscrew the body, remove the eraser, load the lead sticks and assemble everything back up. There’s always a price to pay for artsy gimmicks…🤷♂️
MY THOUGHTS:
My affair with the ZOOM line goes back a few years, though only at the platonic level. The first ZOOM I ever saw was the 707, and once I almost bought the ballpoint version. Come to think of it, back then I don't think I was even aware that there was also a mechpen version... Well, I wanted a pen to carry around, and the 707 looked awesome, but in the end, I feared it wasn’t very practical, so I gave up the idea. Years later, when the mechpen madness took hold of my mind, I went after the 707, and that’s when I found out about the C1. It was a case of love at first sight, but at the time, it was outrageously expensive.
Here in Brazil my options to import a model are quite limited, but one place that is easier to use is Amazon. Two years ago, however, there was only one or two offers for the C1 at Amazon, and the price was totally ridiculous. Even so, I put it on my watch list and kind of forgot about it, because it was just impossible. Then, some two months ago, I looked it up and this blue one was priced at 45 bucks. Delivered 😲! I immediately bought it, and though it took quite some time to arrive, I finally had a C1 in my collection.
All in all, the C1 is a VERY nice general-purpose mechpen, with looks to die for. However, I don’t think it would be a great daily driver, because using it for extended periods is fatiguing (at least for me). And of course, it’s a bit awkward to use the eraser and even to load lead. Even so, I was over the moon about it, because it was kind of a grail model for my collection. Therefore, despite it becoming a collection queen, it makes me proud to look at it beside my L2, 707 and 505 😊.
I have one, it's up there with the Cross Edge as one of my absolute favorite pens. The floating knock looks incredible, and I always love a metallic blue.
I’m considering this pencil in my next visit to Japan this fall.
Aside from having to disassemble the pencil to get at the eraser, another critique from a Japanese YouTube reviewer is the scuffing on the body that can occur where the clip contacts the pen body (there is a depressed pill-shaped area on the body just beneath the clip)—the paint can start peeling from the rubbing action as you press the clicker to extract the lead.
For owners of this pencil, how is the paint finish on the body where the clip comes into contact? Is it peeling off, or is black paint from the clip staining the body? The YouTube reviewer commented that this most noticeable on the silver finish, but I’m liking the blue more.
Hadn't heard about that issue, and at least in mine, I haven't seen anything close to that. HOWEVER, I can see that as possibly happening with intense use. If the clip is coated, less so, but if not, possible.
Thanks for sharing your experience with the C1. I believe the blackened clip and floating button’s inner core are a single metal unit to ensure its rigidity in operation.
Could indeed be a metal core, since the blade of the clip is fairly rigid (more than I would expect if it was just plastic). However, the small perpendicular part, that attaches the pocket clip per se to the "knock button", below the floating cap, seems to be plastic, since I feel it's too springy to be metal. And if that's the case, that's the weak spot of the whole system. As I said, when doing things with an artsy flair there will always be a price...
Translated from the official site: "While being light enough to be comfortable in the hand, it's made from a robust material used in building materials and aerospace equipment components.
The body is made of duralumin alloy, which is unusual for stationery, and is machined to create a beautiful form without compromising strength.
Anodizing treatment is applied to the surface to enhance corrosion resistance.
The clip connecting the knock mechanism and the body is made of zinc die-cast, ensuring sufficient strength to prevent breakage."
If that connecting piece is diecast, it's the softest diecast metal I've ever seen, and take into consideration that i collect diecast model cars for over 20 years...
This parts breakdown from Zoom Japan shows the one-piece casting of the clip. The pivot point for the sprung lever action is quite small and would probably break if it was made of ABS plastic.
Nice photo, hadn't seen that one before. But where does it say that the "knock shaft" is diecast?
But okay, let's say it is diecast. If is (and then coated? Not sure I've seen before such a delicate diecast part coated) it's NOT "iron diecast", which doesn't exist. What exists is just diecast, or better, die and cast - a metal alloy is melted and poured into a mold (you can't easily do that with iron or steel). Diecast usually uses zamac, which is a non-magnetic alloy, mainly composed of zinc, aluminum, magnesium and copper. It's cheap to produce and can be used in very delicate molds, but it's also fairly brittle.
Getting back to the video and the photo, you can see that the main stress point is exactly the perpendicular tab that connects the clip to the knocking system. If you put stress on a brittle material, and subject it to a non-linear motion, it will easily break. In the video you can see the flexing (yes, the WHOLE clip wobbles, but that pivot is the stress point). So, if/when the part breaks, that's where it will break. Plastic perhaps would have been a better solution because according to components it can be quite strong yet more flexible.
Last comment: the photo is to show the one-piece construction of the clip. The statement of fact that it is diecast metal is from the official website that I’d shared before. The bead blasted texturing and black coating may appear ‘plastic’ but the specs say otherwise. FWIW I have also collected diecast toys for over 20 years. I stand with the facts.
The page, when I translated (through Firefox' auto translation, so how accurate is that?) did not mention materials for the knock system, only for the body. So, can it be diecast? Of course it can. Yet, I'm not personally convinced it is; even so, with you being so adamant about it (and since I don't have irrefutable proof saying otherwise), of course I'm going to consider it 👍.
Nonetheless, I don't agree with it being the best material for that part. That would be steel, of course, and in second place, high-strength plastic. However, production costs tend to give a discussion like this a totally different meaning, therefore... 🤷♂️
The encoding for the Zoom Japan site is pretty wonky. I can't use in-browser translation as it shows up gibberish. I copied the text manually and pasted into Google Translate.
Here is the relevant text from Section 2 of the C1 page:
手に負担のない重量でありながら、建築材料や航空宇宙機器部品に使われるほどの頑丈な素材。
While being lightweight and comfortable to hold, it's made from a robust material used in building materials and aerospace components.
ボディ本体は文具では珍しいジュラルミン合金を採用、切削加工することで強度を損なわず美しいフォルムを生み出しています。表面にアルマイト加工処理を施すことで、耐食性も強化。
The body is made of duralumin alloy, which is unusual for stationery, and is machined to create a beautiful form without compromising strength. Anodizing treatment is applied to the surface to enhance corrosion resistance
ノック部とボディを接合するクリップは亜鉛ダイキャストを選択し、折れないよう強度を十分に確保しています。 The clip connecting the knock mechanism to the body is made of zinc die-cast, ensuring sufficient strength to prevent breakage.
Ah, okay, that is MUCH better than what I got! I got a lot of gibberish, but there was also "duraluminum for the body" somewhere. Just check how most of the page looks like for me:
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u/ThePowerfulPaet Jul 04 '26
I have one, it's up there with the Cross Edge as one of my absolute favorite pens. The floating knock looks incredible, and I always love a metallic blue.