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scienceofsharp
Personal blog · scienceofsharp.comscience
scienceofsharp is a personal blog at scienceofsharp.com about science. Since 2019, 16 different Hacker News readers have linked it 21 times, most often “Scienceofsharp”. It is still writing: the last post was on 2025-07-18, and you can follow it by feed.
Too few sampled comments (8) to say how often HN recommends it.?
Why HN links it
A blog on sharpening knives and razors, with SEM microscope images of blade edges, burrs and steel. HN commenters link it as a reference for what sharpness means under a microscope and how sharpening works.
Summarised by Claude from a sample of 8 HN comments that link here. Each comment is marked recommending, critical or neutral (citing without judging); how this works.
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Most-linked posts?
- Scienceofsharp6 people · 6 mentions · first linked 2020-08-08
- Honing rods analyzed with an electron microscope – Scienceofsharp (2018)2 people · 2 mentions · first linked 2025-12-14
- What Does Stropping Do?2 people · 2 mentions · first linked 2022-10-03
What Hacker News says?
These ideas are mistaken. "Sharpness" is related to the physical size and radius of curvature of the apex of the blade, combined with the angle of the terminal bevel. [1][2][3] Chipping of any sort almost certainly tends to erode the sharpness for many reasons, not least of which is that a sharp edge is a very low entropy state (compared to a dulled / chipped / etc edge...). VG-10 steel is considered "entry level" i…
Comment linking /2015/03/24/sharp-and-keen-part-2/
on “How a razor blade can be damaged as it cuts human hair (2020)”Submitted Honing rods analyzed with an electron microscope – Scienceofsharp (2018) as a story · 6 points
HN discussionFor those interested in the SEM images and looking for more, check out this site: https://scienceofsharp.com/home/ The site focuses mainly on sharpening razor blades and is full of SEM images of blades in various conditions. Very cool to see. This page about burrs has some particularly cool images: https://scienceofsharp.com/2015/01/13/what-is-a-burr-part-2/
Comment linking /2015/01/13/what-is-a-burr-part-2/
on “How a razor blade can be damaged as it cuts human hair (2020)”Submitted Sub-surface damage when sharpening steel as a story · 5 points
HN discussionCeramic knives are so prone to chipping that they effectively have micro-serrated edges even when freshly sharpened. A micro-serrated edge on a razor pulls hairs and cuts skin. I don't doubt that in your experience ceramic knives cut food better than metal ones, but I suspect you have not used a well-sharpened knife. Mass-produced knives are typically sharpened using belt grinders and do not cut as effectively as kn…
Comment linking /2018/02/24/ceramic-blades/
on “How a razor blade can be damaged as it cuts human hair (2020)”Submitted What Does Steeling Do? Part 1 as a story · 3 points
HN discussionThere are a large number of electron microscope images here showing the results of various sharpening tools including strops with and without added abrasives. https://scienceofsharp.com/home/
Comment linking /home/
on “How a razor blade can be damaged as it cuts human hair (2020)”Submitted What Does Stropping Do? as a story · 3 points
HN discussionStropping is sharpening. A clean strop (without added abrasive) not only straightens the edge, but also burnishes it and removes material by abrasion. Here are some electron microscope images showing the effects. https://scienceofsharp.com/2014/08/13/what-does-stropping-do...
Comment linking /2014/08/13/what-does-stropping-do/
on “How a razor blade can be damaged as it cuts human hair (2020)”Submitted Misconceptions About Knife Burrs as a story · 3 points
HN discussionObligatory link to the amazing blog about knife sharpness: https://scienceofsharp.com/
Comment linking /
on “Show HN: I built a knife steel comparison tool”Submitted Scienceofsharp as a story · 3 points
HN discussionAbrasion absolutely happens when stropping, however it is very mild compared to other sharpening/honing processes. This is by far the best resource I've found for explaining sharpening and the concepts of sharpness vs. keenness: https://scienceofsharp.com/ I don't go nearly to that level of effort in sharpening, as I only sharpen pocket knives, kitchen knives and various tools, I don't bother with straight razors (o…
Comment linking /
on “Why shaving dulls even the sharpest of razors”Submitted Science of Sharp as a story · 1 points
HN discussionI think the trick with straight razors is to finish the blade with a denim strop with abrasive compound. I only have two stones, a 2k and a 5k. From there, I strop with a strip of denim that I put a little bit of automotive "swirl remover" (it's like car wax with a bit of abrasive in it, but the point is almost any kind of "polish" compound will work.) This blog describes why denim works so well: https://scienceofsh…
Comment linking /2016/04/14/simple-straight-razor-honing/
on “Why shaving dulls even the sharpest of razors”Submitted Scienceofsharp as a story · 1 points
HN discussionI find the best way to think about a honing steel is that you’re micro beveling the edge. [0] The images there help develop an intuition of what angle will work well. That said it may be irrelevant if your universal sharpener is doing the trick. :) [0] https://scienceofsharp.com/2018/08/22/what-does-steeling-do-...
Comment linking /2018/08/22/what-does-steeling-do-part-1/amp/
on “Chestnut Tools Universal Sharpener – Popular Woodworking Magazine (2016)”https://scienceofsharp.com/ is a great contemporary source for how to sharpen stuff, and what that actually means under a microscope.
Comment linking /
on “The Razor Edge Book of Sharpening [pdf]”