Erasers come in a huge variety of sizes, shapes, colours, smells, and a few of them, like the Uni Auto Eraser come in “mechanical pencil” or “stick eraser” format.
The Uni Auto Eraser, model EH-100P, is made in Japan by Mitsubishi Pencil Company Ltd. Essentially it is a basic push top ratchet mechanical “pencil” that propels a 5mm diameter eraser rather than a piece of pencil lead. The mechanism really does feel and sound quite like an ordinary mechanical pencil mechanism.
Aesthetically it’s nothing fancy, just a plain simple round black lightweight plastic body. It’s not unattractive, just a no-frills, no-nonsense sort of look. There are some shallow indent dots at the tip to make a grip zone, and the pocket clip is better than many such integrally moulded clips. The end cap comes off to refill the eraser stick, and it only holds one length of eraser at a time, there are no spares stored inside the body. Eraser refills are seemingly easily available.
From my engineering and general office user background, I’ve traditionally mostly used medium and harder grades of lead, in the B to 2H sort of range. With these grades the Uni erasing power is adequate, but not exceptional. It doesn’t smear the pencil marks, but doesn’t quite seem to erase them as completely as some other erasers do, for example my trusty Staedtler Mars Plastic 526 50. It doesn’t state anywhere what the Uni eraser compound is, but I think it’s vinyl. It is a little crumbly when used, so you tend to end up with a bit of eraser waste spread around your page - it doesn’t easily twist up into a few long strands like the Mars Plastic does. On the other hand, being a 5mm core, it is suited to finer erasing work and you can maintain a reasonably sharp edge for more precise erasing. Now, moving onto softer darker leads, like 2B and 5B, things tend to change a bit. The slight crumbling and thinner erasing face do a bit better than the much larger and firmer Staedtler Mars Plastic. There isn’t as much smearing as with the Mars Plastic, and overall Uni ends up erasing more of the graphite from the paper.
- Best Points – The mechanical pencil look and feel, “pocketability”, and suited to finer erasing.
- Not so good points – The eraser compound is a bit messy for general office work.
Dimensions – Length 128mm, 10mm diameter body. Eraser stick – 5mm diameter x 90mm length, of which about 80mm is usable.
Footnote: You might have noticed that this posting is just called “Uni Auto Eraser EH-100P”, not “Uni Auto Eraser EH-100P Review”. I’ve got a bit of an eraser thing going at the moment and I know I’m going to end up doing a few eraser posts, but I’m quickly coming to realise there is a little more to erasers than meets the eye, (like that crumbling can be good), and that really I don’t know much about erasers, so I’ll just post some thoughts, pictures, information, etc and not be all “formal and reviewy”. Actually there’ll also be some pencil posts in this “informal and non-reviewy” manner too.