These pencils aren’t aimed at writing, yet they are all superb at the task.

Sold to students facing multiple choice exams, they are specialty test pencils. These specific ones are made in Japan, and called “Mark Sheet” pencils.

Of course, test taking isn’t the only possible use, and today we’ll take a look at them from a writing perspective.

The pencils are:

Mitsubishi Uni 100 Mark Sheet pencil, HB
Pentel CBM10 Mark Sheet pencil, HB and B
Tombow LM-KMS Mono Mark Sheet pencil, HB

All are hexagonal with finished caps, and sold unsharpened.

The Mitsubishi is grey, with a black dipped end and blue ring. The lettering is white, and the pencil states, “Hi-Density Lead for Mark Sheet.” The cap is stamped “HB”.

The Pentel is navy blue, and has the slogan, “the best quality for OCR sheet marking.” The blue is offset by two silver rings and silver lettering. The HB has a marigold cap, while the B grade sports red.

The Pentel has a vivid bright blue finish, with a matte silver dipped end and silver ring. The lettering is in white.

All three pencils have nice finishes, and sharpen easily.

Certain pencil/paper combinations really shine (a subject for a future post), and on a Maruman Mnemosyne notebook, all three pencil brands are exceptional in their non-crumbling adherence, smooth application, and dark rich black lines. The best? For me, the Pentel, and especially the B grade version, stood out as a super-smooth writer.

Specialty pencils of course have specialty erasers, and the Uni Mark Sheet eraser does a great job. The formula seems somewhat different than other familiar erasers from Pilot or Tombow – more crumbly, but possibly even more effective.

(Pentel also make a “mark sheet eraser”, but I haven’t seen it in person.)

All are first rate, but writing with the Pentel CBM10 Mark Sheet pencil in B is an experience I especially recommend to all pencil users!

See also:

Pentel Mark Sheet Pencil – pencil talk, August 2008
LM-KMS – Lexikaliker, June 2009
MONO Mark Sheet Pencil Set – On the desk, at any time, March 2010

Though Pentel may be known for mechanical pencils and lead refills, their woodcase pencil products are equally outstanding.

In our lineup today, we have:

The Pentel Mark Sheet pencil is Pentel’s entry in the test scoring category. In HB, the pencil is dark blue with silver lettering. The cap is dark yellow/light orange. As a pencil, it is astounding. It sharpens easily, and writes incredibly smoothly, leaving an extremely deep, rich, saturated line – that is also erasable.

The pencil was not an entrant in last year’s test of the top Japanese pencils, but it might have been a contender. It is just amazing!

The TUFF pencil is a mystery to me. In grade H, it writes very nicely. I think it would be extremely satisfactory for someone seeking a pencil that keeps a sharp point, and writes smoothly, with a line as dark as most mainstream HB pencils.

Next, we have a turquoise version of the Pentel Black Polymer 999. The pencil has a turquoise finish and Japanese language text. Automatic translations of Pentel literature call this a “pencil for copyist” or “copyist pencil”. Perhaps someone can advise?

The space for a name on the side of the pencil suggests it is for students.

What I do know is – it is a fantastic pencil! The smooth writing qualities just amazed me. It’s nice on cream paper, but on a white paper like Clairefontaine or Rhodia, the dark rich graphite just pops! My only reservation is the turquoise colouring, which I am not sure I like.

The “regular” Pentel Black Polymer 999 in HB is another well known top pencil. My growing impression is that it trades just a bit of smoothness for deep blackness, without the production of crumbles. The 4B in the series is quite amazing, creating super saturated black lines. What’s in the pencil? Is it a “polymer lead”? Stay tuned … I think we’ll learn more in the future.

The Pentel Black Polymer 999? is the top of the line. In H, it would be fine on bright white apper. I think it is quite a bit smoother than the TUFF, the other H grade pencil. It also boasts an extremely nice black lacquered finish. Though there is too much text for my taste, it is a very classy looking pencil.

We’ve heard that Pentel isn’t a woodcase pencil manufacturer per se – they subcontract their production. What can we say? Well done! The only possible criticism I can think of is that they don’t have as full a range of grades as their competitors. But everything they have done is first-rate.

The online Pentel 2009 catalogue shows the Pentel Black Polymer 999, Pentel Black Polymer 999 Copyist, and Pentel Mark Sheet Pencils. The others may be discontinued.

Nice pencils, Pentel!

The pencils were shown on a Mateo Ilasco No. 309 “Blueprint” notepad, and sharpened with a Carl Decade DE-100 sharpener.

My thanks to isu from the uncomfortable chair for kindly sending me the majority of these pencils.

Hmm, has anyone noticed this aspect of mechanical pencil refills?

Pentel Ain refills (just to pick a particular brand) are all the same price.

And all are 60mm in length.

But they contain:

0.3mm – 20 pieces
0.4mm – 30 pieces
0.5mm – 40 pieces
0.7mm – 40 pieces
0.9mm – 36 pieces

What gives? Thinner lead costs more? I would think one would get more pieces of thin lead per dollar.

If you calculate volume = length * pi * radius * radius

Then single pieces of lead are:

0.3mm = 60mm * 3.14 * 0.15mm * 0.15mm = 4.24mm³
0.4mm = 60mm * 3.14 * 0.20mm * 0.20mm = 7.54mm³
0.5mm = 60mm * 3.14 * 0.25mm * 0.25mm = 11.78mm³
0.7mm = 60mm * 3.14 * 0.35mm * 0.35mm = 23.08mm³
0.9mm = 60mm * 3.14 * 0.45mm* 0.45mm = 38.16mm³

That’s right – a 0.9mm lead is 9 times the volume of a 0.3mm lead! (Which makes sense as the volume is proportional to the square of the three-times-larger radius.)

So as to how much lead is in a Pentel Ain box:

0.3mm: 20 * 4.24mm³ = 84.80mm³
0.4mm: 30 * 7.54mm³ = 226.20mm³
0.5mm: 40 * 11.78mm³ = 471.20mm³
0.7mm: 40 * 23.08mm³ = 923.20mm³
0.9mm: 36 * 38.16mm³ = 1373.76mm³

That’s right – for the same price, a 0.9mm user gets 16 times more lead in a box than a 0.3mm user!

Curious?

Here are a couple of amazingly thin erasers.

The Tombow Mono zero is a 2.3mm diameter cyclindrical eraser, dispensed by clicking the cap. It really does seem like a mechanical pencil in both form and function.

I thought this eraser was probably a borderline novelty, but it worked quite well over a period of days. You wouldn’t use it to erase several lines of text, but it is great for smaller tasks such as changing a line fragment, digit or letter.

I like the portability as well.

The Pentel Clic Eraser Hyperaser is a rectangular metal housed eraser. It has a dispense mechanism similar to that of most stick erasers, such as the Staedtler 528 50. A clip as well!

This is an ink eraser. It seemed to work well on tests with ballpoint ink, and less well with fountain pen ink.

I wasn’t expecting much, but both seemed pretty good.

The main problem I see it that both require yet more proprietary refill types. The Mono zero in particular seems like it will require a replacement eraser soon enough.

My thanks to der Lexikaliker for the Pentel eraser.

We’ve seen special pencils aimed at optical and electro-mechanical mark recognition – the vintage IBM Electrographic, and the more recent Musgrave Test Scoring Pencil.

Quite a few people seem to be interested in these pencils, so I’m pleased to be able to mention a superb modern example that I recently learned about – the Pentel Mark Sheet pencil.

This hexagonal pencil is finished in blue with silver lettering. Two grades exist – HB, which has an orange cap, and B, with a red cap.

The pencils are marked -

Side 1: Pentel Mark Sheet Pencil HB

Side 3: the best quality for OCR sheet marking CM10 Japan HB

Side 5: [bar code]

The lead is just superb – at the pinnacle of modern graphite quality. The pencils leave extremely dark, rich lines. There is often a crumbling issue when a pencil’s graphite saturation reaches this level, but these pencils have no such problem.

It would be hard to imagine a better performing pencil.

In our previous review of top Japanese pencils, it was lamented that the Pentel Black Polymer 999? was unavailable. We did review, and have previously looked at, the second tier 999. “Second tier”? The 999 is without doubt one of the finest pencils ever made, so we’ve been extremely curious about what Pentel considers to be even better!

There are now a few vendors that sell Japanese pencils internationally. Despite numerous enquiries over a period of years, no vendor we’ve contacted has been able to obtain this pencil. The only online evidence that this pencil ever existed seems to be a few small photos and statements here and there. With thanks to the resourcefulness of isu of the uncomfortable chair, it is now possible to finally examine this pencil.

In grade ‘H’, two pencils were obtained. Here we invoke the ‘to have and to hold’ philosophy – keep one ‘as is’, and use, enjoy, test, write, with the other.

Pentel does not have their own woodcase pencil production facilities – these magnificent creations are apparently all subcontracted. Well, Pentel must be a first rate contract manager, because their products have turned out very well.

The 999? is a glossy black pencil with silver lettering and accents. The varnish quality is excellent.

Following previously introduced nomenclature -

The obverse reads:

Pentel Black Polymer 999? H

And the reverse:

supreme quality for drawing lines of high density CB200 JAPAN H

The pencil cap itself seems highly curious – possibly some sort of plastic or resin.

“Supreme quality” is a major boast, but if any company could deliver, it would presumably be Pentel, known for many lead and mechanical pencil achievements.

It being a pencil that likely exists in limited numbers, one was carefully sharpened in the “regular” slot of a Tombow SM-200WN sharpener.

It sharpened to a very fine point – which after several days of occasional use – has not yet broken.

‘H’ leads are outside our usual frame of reference – we know they are useful for many drafting and drawing purposes, but are typically harder than we would prefer for general writing/sketching.

To establish a context, two Staedtler Mars Lumograph 100 pencils in H were also tested – one new (silver lettering, bar code), and one perhaps five to ten years old, with white lettering and no bar code.

The two Staedtler pencils did not seem the same – the older one appeared to leave a fainter line.

Compared to either Staedtler pencil, the Pentel seemed to leave a richer, darker line, and to be extremely sturdy – combining a fine sharpening capability with great non-eroding durability . If ‘H’ pencils generally came like this, they would be loved by many.

Drafting-only pencils are somewhat out of our element, but nothing observed indicates that the 999? isn’t indeed of ‘supreme quality’.

Distinguishing the two pencils is easy – the 999 alpha has the Greek alpha character in the pencil name, and the slogan “supreme quality for lines of highest density.” It has a glossy finish with the grade printed in black on a silver background. The regular 999 has the more modest slogan “the highest quality for general use”, and less use of silver. The finish is matte, and the top of the cap is painted silver.

Matte vs. glossy sounds like a photo finishing or interior wall paint choice. But it seems it’s also a pencil choice, and Pentel chose matte for the 999. It is very pleasant to hold, looks good, and is not too common in pencils. I have some Lyra pencils with a similar finish, and can’t think of any other manufacturers that have chosen this type of finish. The silver accents on black paint make it one of the most attractive on the market – up there with the Grip 2001 and Nava.

The box it comes in also looks nice for a cardboard box – there is something very adult and stylish about the presentation.

The pencils sharpen easily. The lead is not as rich as that of the other Japanese pencils mentioned here, but still nicer than average. It makes an excellent writing pencil, and goes very nicely with a black journal.