Some Birds

The winter has raised its ugly head once moar, there is about 5 cm of snow outside and it is freezing cold outside for several days by now all night and most of the day too. The one and only upshot of this is that after a very long time, I got some variety of birds on the bird feeder again. I haven’t posted any pics because I basically had only three species on the feeder and absolutely nothing else – house sparrows, great tits, and blue tits – so I did not even take the camera out for months. In fact,  I could not even find my camera because I gave it a new home during my PC repairs at the start of the year and I forgot where I put it.

Babbling aside, I got pictures of increasingly rare visitors – goldfinches, siskins, and also bullfinches.

© Charly, all rights reserved. Click for full size

© Charly, all rights reserved. Click for full size

© Charly, all rights reserved. Click for full size

© Charly, all rights reserved. Click for full size

© Charly, all rights reserved. Click for full size

The male siskin has a huge evergreen holly in the background so it looks like the pic was taken in nice warm weather in the summer instead of the frikking frigid freezing winter.

There were also jays, greenfinches, and chaffinches but unfortunately, I did not manage to take a shot of those. It is good to know at least that they are still around.

The bad news is that all above mentioned species were present in significantly smaller numbers than in previous years.

Coppice Harvest

I wrote previously that I am trying to use my needlessly big garden to grow firewood in a coppice. It would be a great success if not for water voles who are a sworn enemy of anyone growing any trees for any purpose. However, these last few days were warm-ish for winter and thus I had the opportunity to not be an utterly useless lump of meat for a few days – I cut down the coppiced/pollarded trees and sorted most of the wood into piles. Twigs for the shredder, thinner trunks for growing beans in the summer and being cut into firewood afterwards, and thicker and/or crooked trunks to be cut into logs right away.

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It looks more than it really is, the volume will be significantly reduced once the twigs go through the shredder. I estimate it to be approximately 10-15% of my yearly use of firewood. Blast the voles, without them, it would be probably around 50%. They even destroyed multiple of my established 3-5-year-old trees, so the coppice did not in fact grow bigger since 2019 at all and it is entirely due to voles. They destroyed approx 70% of the planted hornbeams, and nearly 100% of the poplars this area of my garden is not wet enough for the willows to prosper so it is still useless land that needs to be mown and is of no real use to anybody. I have started to plant local maples, ashes, birches, and hazels instead of the poplars but those get often destroyed by voles too and they do not grow even remotely as fast. Fuck the little fuckers. Did I say I hate water voles? I hate water voles.

But the work made me feel well. I really needed to go outside and do something during daylight.

Sciencing Sharpness – Part 5 – My Sharpening Kit

I have found a blunt-ish knife, one that I use in the cellar to open wooden briquette packages. It was not exactly blunt but it was slightly blunt and I have run it over a quartz stone to make it blunt. It is a knife from high-quality stainless steel but it has been sharpened so much that it has lost about 30% of its width. I have tested with it my traveling sharpening kit. I have done completely freehand sharpening, holding the stone in my left hand and knife in the right hand, no angle measuring, not even angle estimating, just putting the blade to the stone in a way that “feels right” and going on from there like I used to before I got the machinery to be precise. I tried to look up on the internet the grits of the stones that I use but it ain’t easy because one of them is a no-name generic grey carborundum whetstone and as you will see, it does not appear like I found the right ones. I have also used all of the orange thread that I have reinforced with PVA glue and from now on I will use the nylon thread since I have already bought it.

Here is the picture that’s worth a thousand words:

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And here are less than a thousand words explaining what’s in the picture:

It is a bit strange that the fine grey layer of the cheap whetstone does not perform much better than the coarse layer and even performs worse than the beige layer on the colored stone which should have slightly coarser grit. There are several possible explanations or a combination thereof – I got the grey stone grits wrong, I done did do a bad job with this layer, or the fact that this stone uses a weak binder and sheds grains very easily plays a role, or I messed up the measurements. Nevertheless, the knife was capable of cutting freely hanging printing paper at this point, although not very easily, and it did bite into a fingernail.

Anyhoo, the second stone is much harder and I actually know the exact grits from the manufacturer. And once I got to the red layer with “just” 500 grit, the knife was shaving-sharp. The leather strops might have burnished the edge a bit but there is no statistically significant difference anymore from the 500 grit stone. It looks like there might be one, a very minor one if I had performed more measurements or had a more precise method.

I would say that it is pretty convincing for my argument that a two-layer whetstone and a strop are all that is needed to get and keep knives sharp.

It also appears like 500 grit stone is sufficient to maintain a knife edge shaving sharp without any further ado. But I would say that shaving hair with the stropped knife feels slightly “smoother” on the arm than with one that went just over the stone and I feel inclined to trust my skin sensors (they are much more sensitive than the kitchen scale after all) on this issue so I’m not convinced that the strop is completely useless. Measuring as fine differences as these might be is not a task that can be done with a rigged-up kitchen scale.

Sciencing Sharpness – Part 4 – Failing to Improve the Measurements

My mother was ordering some things from an online drugstore and I jokingly said if she could order me a nylon thread too. And surprisingly, the shop did carry a 0.25 mm nylon thread. It arrived today. I have immediately run an experiment to evaluate if it delivers better results than my old, PVA glue-impregnated thread. And sadly, it does not.

I made 25 measurements with both threads with a razor and then with the testing knife sharpened at 10°. And the results are interesting, but not good.

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The nylon thread performed statistically significantly better for the razor – the values were less spread out. But when it came to the knife they were both about the same, with no statistical significance whatsoever. And there were outliers in both sets. A disappointment, really. A lower spread would allow me in the future to get useful results with fewer measurements per each test, this way I am somewhat stuck with making at least ten measurements.

At least all four sets had normal distribution which means that averaging multiple measurements should give precise-ish results.

I think that the biggest problem is the scale’s lack of a Hold function and the frequency at which it renews the display. Well, it is still useful and the thread did not cost too much. And it is easier to span.

Sciencing Sharpness – Part 3 – Angle vs. Sharpness

It is not good for my ego to have the predictions mostly correct again, but this time there were things that surprised me a bit.

I have included a sharpening angle of 10° which I never use in praxis because it is not recommended for the N690 steel due to reduced edge retention at that angle (tendency to chipping), but that would not be a problem in this test and it is a data point of knowledge in case I make some carbon-steel sushi knives or razors in the future.

Now the boxplot:

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So I got the prediction about how the cutting force will rise mostly correct. Mostly, not completely.

ANOVA test has found no significant difference between the first four angles but I am sure there would be one if I had performed more measurements and/or refined the testing method. The Lookandsee test does indicate a slow rise in cutting force from around 25 gf to around 50 gf.

The jump at 30° is a bit more sudden than I expected. I suspect that it is a fluke. And then the rise at 40-45° was a lot less than I expected.  It seems that the 90° cutting edge is still significantly better than no cutting edge, which would be somewhere around 3-4 times worse with a cutting force of around 1000 gf. I did not expect that. The best-fit function is quadratic. This is less drastic than the predicted exponential growth, although still significantly faster than simple linear growth.

So in conclusion, it does appear that my opinion that whilst there is a difference at angles 10-25°, it is not big enough to matter for casual knife users is substantiated. The angle 30° performed slightly worse than I expected, and the angle 45° performed significantly better than I expected.

I am going to think about all this some more and then I decide how to proceed from now on.

Sciencing Sharpness – Part 2 – Grit vs Sharpness

Notwithstanding dangerousbeans’s comment at the last article, I did find in my steel offcuts pile a blade that broke after it was nearly completely finished, with etched logo and all. That means learning about the sharpening properties of exactly the steel that I use in exactly the state it is in a finished product. In different steel, the results might come out a bit differently, which means I am mightily glad that I could do my tests on this – an absolutely ideal testing specimen.

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I have sharpened the blade stub at a 15° angle which is the angle at which I usually sharpen kitchen knives, and always those that I make from N690 steel. (When tasked with sharpening store-bought knives from unknown steel I occasionally sharpen them at 20°, especially if it is clear from the state of the knives that the customer is not particularly careful about their use.)

I established the bevel with 120 grit and then I progressed from 180 and 240 grit Zirkorund and then Trizact belts (in the evaluation translated into grit equivalents) from A 65 all the way to Trizact A6. I only differed from my usual sharpening procedure in one way – I used fresh belts, instead of old ones. Normally for sharpening, I am using old belts because sharpening is extremely rough on the belt and destroys it very quickly.

The measuring method is wildly imprecise – the testing thread is not homogenous, the angle at which I put the blade on it is not always precise, I do not always hit the center, I am not pushing with constant speed, the kitchen scales do not renew the measured value with sufficient frequency and probably several other variables. I have experience with such measurements from my previous job though and there are ways to get relatively reliable, reproducible, and usable results even so. One of those ways is to make lots of measurements – that is why I took 12 measurements, discarding two of the most egregious outliers and making the evaluation with the remaining 10. There are mathematical methods for discarding outliers but for my personal purposes, the Lookandsee method suffices. (Thirty or fifty measurements would be better, but I am not going for exact values for individual grits, I am going for a comparative assessment between those grits. Anyway, not going to write a boring lesson about measuring).

Here is the boxplot of those ten measurements per each grit:

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And it looks like my prediction from yesterday was bang-on. Which is satisfying to my ego, but also boring in a way. It would be much more exciting if it were different.

What you see here is the cutting force going rapidly down from ~270 g at 180 grit to ~ 75 at 400 grit. At this point, the blade is capable of cutting freely hanging paper. Then it falls some more to ~40g  at 800 grit and more or less stays there till the end (the knife is shaving-sharp at these stages). The slight increase at 1200 is a fluke that would most probably go away if I have made more measurements and/or invested time and resources in refining the method. I made ANOVA test and there is no statistically significant difference between the last three fine grits.

So in conclusion, sharpening knives beyond 1000 grit indeed appears to have very little practical value. At 800 grit the blade is already shaving-sharp and polishing the edge further only costs more time without noticeably improving its cutting capabilities. With more precise measuring method there might be a difference, but it would be very, very tiny. I think that I can replace the last two belts with a leather belt infused with stropping compound and get the same result. And since time is money, I will do exactly that.

Sciencing Sharpness – Part 1 – Predictions

I hope to use my new sharpmeter to get some knowledge about, well, sharpness. And since I am going to be playing at science whilst doing so, I have decided that I will write down the predictions for my tests. The tests will not be blind, because I will be doing both the sharpening and testing and there will still be some subjectivity to these tests, but nothing is perfect. I am doing these tests to gain some knowledge and I will share that knowledge for free but there will inevitably be bias.

The first test that I intend to perform is the influence of grit on edge sharpness. I think that after establishing the bevel with 180 grit the cutting force will go down significantly with the next steps, but it stops changing significantly above 400 grit. My reasoning for this is the fact that it is possible to get a knife shaving-sharp with ca 320 grit stone and at 320-400 grit usually the wire edge/burr falls off. I think that I have mentioned in the past in comments somewhere – either in Marcus’s place or here – that going above 1000 grit in sharpening makes little sense function-wise, although I cannot find the comment now. I will go up all the way to trizact A6 belt (the equivalent of 2000-2500 grit) in the experiment.

The second test that I intend to take is the influence of the sharpening angle. There was a heated debate between me and Marcus on this issue a while back -click-  and I really want to test it (caveat from the first paragraph applies doubly). I expect the force needed to cut the thread to rise exponentially, i.e. slowly from 10-25°, then some more for 30° and even more for 40° and again even more for 45°. I won’t test sharpening angles steeper than 45° because it makes no sense IMO since a 45° sharpening angle means a 90° edge. I know from praxis that knives sharpened at 15°, 20°, and 25° can be shaving-sharp. I do not know much about the 30° angle, since that is extreme and I only sharpen hatchets and axes at that angle and I never even tried to get those to shaving-sharp. They do cut paper though.

So, sometime this week I shall heat the workshop again, sharpen some steel offcuts (probably pieces of old hacksaws) and go measuring.

Sharpmeter

It is freezing here and I still do not have the slightest inclination to do something useful. But I need to heat the workshop occasionally to prevent it from completely freezing. Not that it would be super bad, except that maybe ice forming in the cooling receptacle near the grinder could damage it. Anyhoo, yesterday was a workshop heating day. I could not do anything super useful – it took me hours to raise the temperature to a bearable level and soon after I stopped feeding the stove, the temperature got down quickly again. But I could use the time to do something small and simple so I have made a device for measuring knife sharpness (I did not invent the concept, I saw the principle somewhere on the interwebs sometime ago).

© Charly, all rights reserved. Click for full size

It is simple and consists of two main parts. One part is a board with four legs and a 35 mm hole in the middle. A tiny table that can be put over my kitchen scales.

© Charly, all rights reserved. Click for full size

The second part is a small wooden cylinder with a cutout and two screws on each side of it.

© Charly, all rights reserved. Click for full size

I can span a thin thread between the two screws and when the cylinder is put on the scale through the hole in the middle of the tiny table, I can cut the thread safely for me, the scale, and the furniture.

The main downside is that my kitchen scale does not have a “Hold” or “Max” function so the measured values are not super precise. Another problem is the used thread – a very thin fishing line would be probably better since this one has a tendency to get damaged during spanning. Or perhaps a very thin copper wire – I might try to extract some strands from leftovers from speaker or ethernet cables. But when being very careful with spanning the thread and doing the cut slowly and carefully, the setup gives useable results and I did learn some things.

Here is a boxplot of 10 measurements with the three cutting implements in the photos – a fresh razor blade, a paper-cutting-but-not-shaving-sharp sharp knife, and a blunt table knife (I used the non-serrated part which is about 1 mm thick),

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The razor had an average cutting force of ~6 g, the sharp-ish knife ~60 g, and the blunt knife ~ 1000 g. The less sharp the blade the bigger the spread but even with sometimes ridiculous outliers, there is a definitive and statistically significant difference between these three and it does give me some information and opens future opportunities. I would like for example to examine the relationship between sharpness and sharpening angle, to get some hard data to back up my opinion that anything between 10-30° works just fine. My prediction is that the relationship is not linear and as the angle gets steeper, the cutting ability gets exponentially worse.

I did learn one thing – my “Not a Masterpiece” was sharpened at a 20° angle and the only knife that actually scares me – the bigger knife from the two-knife applewood set – was sharpened at 15°, yet both measured within the same range as the razor. Although the applewood knife completely failed to register on the scale one time, thus my suspicion that it is the sharpest knife I made so far might be true.

Of course this only tests edge geometry, not blade geometry. I could use a similar setup to test the influence of blade geometry on cutting force too, but I do not have a reliable medium to do so yet. All things that I have thought of so far are either expensive (cork, rubber, silicone) or have highly inconsistent properties (fruit & veggies). But maybe I will think of something to test blade gomtry too.

Women Crafter on Youtube – Knitter – Engineering Knits

My mother used to knit and we still have two straight knitting machines of a solid metal build. I did learn how to knit as a child but I already forgot it all and it is unlikely that I will ever need it. My mother-made sweaters have served me well for years by now and I expect them to continue to serve well for enough years to not need a replacement.

She has also knitted several pairs of thick socks that come in handy on winter travels when I need to sleep in some poorly heated room. Or when the winter is so cold that despite heating, sitting at the PC gives me cold feet. But we do not have a circular knitting machine, all the socks she has made had to be made by hand. Thus I have enjoyed watching a circular knitting machine in action because that was the first time I saw it.

Pity the machine seems to be made of cheap 3D printed plastic. It won’t have the durability that my mother’s knitting machines have – those are still fully functional after decades of intensive use.

If you are interested in knitting and its history, Engineering Knits has a lot of videos on that topic.

Project Phoenix – Part 5 – The Tail Finished

Here you can see most of the tail with most feathers finished.

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The tail is completely finished now. Each feather, whether big or small, took me over two hours to make, so with all the prep work, etc. about twenty hours for the whole tail. The reason why small feathers took nearly as much time as the big ones is that what I wrote previously – the narrow long straight-ish part starts with eight bobbins but the ends are 16 bobbins of different colors so it is not exactly easy to keep track of them.

I started doing the wings too, but I had to stop the works for a few days again because I am depressed as hell and it is difficult enough to get out of bed and heat the house, let alone do something on top of that. I started the wings in red, did not like it, and had to undo it. So here is a picture of undoing the lace. It is the same as doing it, except going in the opposite direction.

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I did not like the red color directly near the red body and I also did not like the weave being so tight. I have used a very tight weave on the head and neck, but I won’t be using it on the wings because I think the wings will look better with the thread pattern being more obvious. If I won’t like the result, I will have to undo it again.

Crypto, Scams & Ableism

Since the Scam Banking Fraud fiasco in the crypto world, I have looked a bit more into cryptocurrencies and NFTs. Not much, just to satisfy some curiosity. That curiosity brought me to the YouTube channel Coffezilla (which I recommend). And today I would like to mention a bit unsavory and unfortunate thing that crops up in just about every discussion about cryptocurrencies and associated scams – comments along the lines of “People this stupid deserve to be scammed”. Sentiments akin to this are very prevalent and I must say, I disagree with them now although I do have an inner tendency towards such thinking too and I have to reason myself out of it in some specific cases and I would possibly say these things too about twenty-five years ago.

Why is that? I mean, why is this sentiment so prevalent? I do not know of course, but I can speculate.

I think it is in part because a lot of people in the west are conditioned to believe in the Just World Fallacy. In most fiction, the villains get their just desserts and the good guys more often than not win. We are taught that hard and honest work is rewarded and that crime does not pay. This cultural bias is everywhere and unavoidable. And it is inherently ableist because no matter how difficult it is to actually meaningfully measure intelligence, it does exist, it does wary among people and some people are innately, with no fault of their own, less capable and thus more susceptible to being hoodwinked. There is a reason why so many e-mail scams have appallingly bad grammar and spelling and why so many phone scams are targeting elderly people.

It is not all though. Another part of this is in my opinion that a lot of people enjoy the warmth of a slightly smug feeling of being superior to someone in some way. “Haha, how those poor suckers could fall for THAT.” This is understandable to some degree in insecure people who are still finding themselves but not appropriate for well-adjusted adults. As for myself, today I have plenty of personal experiences to put me down from my pedestal whenever I feel like climbing one – the most recently my tribulations of obstinately plugging the wrong cable into the wrong hole for two days and wondering why things do not work. I know I am not completely stupid and still, my brain sometimes does things that a duckling would deem daft. Not to mention the GIGO principle, which can lead even the best of the best minds astray.

And even when one knows that the world is not just and that smart people can do daft things for a variety of reasons, I guess many people also know at least someone who is definitively willfully stupid and simply cannot be reasoned with because they refuse reason on principle. The most egregious examples of these people are all those creationists, flat-earthers and Q-anoninsts out there. But is it OK to say that someone deserved to be scammed because they ignored warnings and information given to them?

I still don’t think so. If they really were given credible warnings and ignored them for example, then they are to be blamed at least in part for their misfortune in such a case, but they do not deserve it. Saying that someone deserves to be scammed implies that scamming is an act of justice.

It is not. It is an act of malice, a betrayal of trust, and nothing is gained by it. The victim may become less naive and trusting as a result, but that is only a good thing in a society where there are scammers. And whilst being naive and trusting is unwise in our world, it is not malicious or harmful, and punishing it thus makes no sense. A scammer deserves to be judged and locked up. A scammee deserves help.

I’ve Been Cursed, Surely

Last year my projector stopped working. That was unpleasant, but I can live without it, I haven’t really watched a movie for a while. Then the trouble with the processor. Yesterday my gaming headphones stopped working too, for reasons unknown – I haven’t been using them that much.

And to top it all off, I still cannot get the sound to work on my PC. First, the onboard sound card just refused to work and since that problem has been noted by multiple people on the Internet, I have decided to stop trying to solve it and buy a new sound card.

At first, the system did not recognize the new card at all. Then for reasons unknown to me, it recognized it and I could install it, but it does not work properly. I only have stereo sound. When I set 5.1 sound, only the front left and right speakers work, all the other ones remain silent. I am still reluctant to try a blank windows installation because I am not convinced it would help with this.

I am frustrated and tired and depressed.

Rough Start of a New Year

I was backing up my data on Sunday when my PC suddenly shut down. Then again. And again.

I identified the problem – the CPU was overheating because I was creating ZIP files which taxed it more than my usual work. No biggie, I told to myself, I will vacuum the dust from the case and apply new heat conducting paste between the CPU and cooler, that should solve it.

Well, it did not go as expected. When trying to remove the cooler from the CPU, it pulled the CPU from the motherboard. The conducting paste was so old and dried-up that the two components were essentially glued together. And when trying to separate them, I have broken off one pin from the CPU, destroying it. That has never happened to me, but everything is for the first time sometime, I guess.

That was a very expensive mistake to make. The CPU was 11 years old which means buying a new replacement was not an option. I might get my hands on a second-hand one if I searched enough, but there would be no guarantee of functionality. Thus I had to buy a new motherboard and RAM as well. I ordered the new components yesterday morning and I spent the afternoon using my notebook to extract sensitive data from my system HDD just in case I need to completely reinstall my system.

Today the components arrived, I have re-build the PC and after some false starts and learning some new stuff (last time I have build a PC was three years ago), I was able to successfully boot into my original system. I have lost no data and HW-vise the only remaining problem is to get the audio work. I wanted to make bobbin lace and instead of that this.

Well, it could be worse.