Making Kitchen Knives – Part 3 – Basic Grind

This is the part where work on more blades in parallel is no more possible, but I have tested an improvement that I have hoped for to both save time and increase precision. Grinding symmetrically free hand a blade mere 1,8 mm thick would not be easy. My previous knife of this type was made from 2,5  mm steel and I messed up the grind. I have spent more time correcting my messed up grind than I liked to and in the end I had to opt for a blade without a clear transition between the blade and a ricasso.

©Charly, all rights reserved. Click for full size.

I wanted to do better this time, so I have built an experimental jig. As you can see on the picture, it is a simple 30×50 mm block of hardwood (a leftover from building the belt grinder). Two screws hold the knife on the smaller side, and three screws are right on the edge opposite the knife. Those three screws pop out a bit out of the wood and by how much they pop out is how big an angle I have between the blade and the platen on the belt grinder.

©Charly, all rights reserved. Click for full size.

I did not make a picture on the belt grinder, but you can see on the right the jig with a blade put against a machinist’s square. The advantage of this setup is that if I want, for example, ~0,3 mm thick edge before hardening and with the blade being ground all the way to the back, I know that I have to set the jig so that there is ~0,70 mm between the square and the back of the blade. Which is exactly what I have done, only without measuring, only eyeballing the gap and deciding “yup, that is what I want”.

The jig is set up so that I can screw the blade in two mirroring positions, but I did not bother too much with precision, because I did not know yet whether it will work or not.

It worked, but the imprecision was abit of a problem, as well as the way the blade is fixed. Two main problems occurred:

  1. The tip of the blade lay on the supporting table. That proved to be a problem, because it got snatched by the belt and dragged into the gap between the belt and the table. It messed up the grind in split of a second and I have spent no trivial ammount of time correcting it.
  2. Changing the blade on the jig took way too much time, even with accu-screwdriver. Part of the problem was the imprecision, because I had to monkey with it each and every time to get it right.

So a more precise jig that allows fro quicker change is required, and it also should hold the blade at least a few mm above the supporting table for better control. As a proof of concept it worked, it did indeed improve precision, but there is potential

During the grind I have made one time-wasting mistake, but I did not know at the time it is such. After I have established the grind with ceramic belts which go up to 120 grit, I continued to 240 grit on Zircon-carbide belts. As it turned out,  I could have spared myself those zircon belts alltogether, but more about that next time.

©Charly, all rights reserved. Click for full size.

I forgot to make a picture of the ground blade, but here you can see it as it went into the next step in the process. You can see that I have managed nice clean line all the way to the back of the blade, which I was previously not able to do free hand.

The time spent with this was about 1:15, or 75 minutes. From that time I have spent approximately 10-15 minutes monkeying around with fixing the blade on the jig, and another 5-15 minutes changing belts on the grinder. I also wasted some time correcting messed up grinds. I think that a better jig and above all not going above the ceramic belts should cut this time in maybe a half, but probably not more – it is fidly work and probably the biggest factor is experience. I remember Walter Sorrels saying in one of his videos that he manages this in 10 minutes, but only because he has been doing it for years.

Right now I am putting it into the “low hanging” fruit basket, because I think I can easily get a significant 15-20 min improvement through better jig and not going too fine with the belts. The rest is, unfortunately, entirely dependent on how fast I will scale the learning curve.

Making Kitchen Knives – Part 2 – Draw, Drill, Cut

©Charly, all rights reserved. Click for full size.

Each bar I have is big enough for two knives, but I cannot simply halve them – there is nearly 10 cm overlap towards the tips. That way I get longer knives whilst wasting less material. I have made a new paper template and here you can see how I laid it on the bar. To draw the outline I covered the whole bar in blue color using very thick (1 cm) marker. A much cheaper and more readily available option to machinist’s blue. You can also see that  I have lost my drawing needle somewhere in the 10 square meters of my shop so I have made a new one from an old shuttle bobbin. I hope I won’t lose it too.

When doing this I have wanted to test an idea how to improve my process already, so I have made another template which allowed me to mark not only the two holes for pins, but also a hole at the center of the finger groove. Unfortunately I did not make a picture of that.

©Charly, all rights reserved. Click for full size.

But here you can perhaps see why the third hole. After marking the hole positions with a center punch, I proceeded to the drill. But instead of a normal drill bit, I have spanned in it a step drill which allows me to drill holes from 4 to 22 mm. So I drilled 6 mm holes for pins and an 18 mm hole where the finger groove is. That way I do not need to mess around with some improvised way to grind a nice tight radius that I need. This is a big time and hassle saving in itself.

This is also first significant change in design to the prototype that I have given to my mother. She did not exactly complain, but she commented that a deeper finger groove would be more comfortable. So I am making the groove deeper and therefore the handle inevitably skinnier in this part.

©Charly, all rights reserved. Click for full size.

I have marked and drilled both halves, then I cut the bar diagonally with an angle grinder. Using an angle grinder I have also cut excess metal on both knives since I live by the rule – if you can cut it, do not grind it.  After that I have tried another time-saving measure that I have thought up in my idle time – I have connected both knives with screws through the pin holes. With that I proceeded to the belt grinder to grind the outline of the blades.

It worked very well and I had outlined two knives very quickly, in fact these three steps took a lot less time than I expected – just one hour overall. And I even see big time-saving potentials here:

  1. For drilling I could make a template for guiding 6 mm drill bit instead of punching the holes for each blade separately. So for next run I will first fish around in my scrap pile if I find a scrap piece of the right shape and size. Then I can stack and drill more pieces in one go. I will lose some time by stacking, but save time drawing and punching. Also next time I will first drill all stacked pieces with a 6 mm drill bit for the finger groove as well. That means changing the bit once, but I think it will be more than made up by the time saved from drawing and punching.
  2. I can probably stack at least two, maybe even five, pieces before cutting all the excess with the angle grinder.  Five pieces would be 9 mm thick, and an angle grinder should be able to grind through that without big trouble and without too much reduction in speed. And I will waste less time per blade by repositioning the piece in the vice for each cut.
  3. Ditto for the belt grinder. A new 40 grit belt should be able to grind five pieces at once with only marginal reduction in speed. That would also improve reproducibility.

So I am putting this in the “low hanging fruit” basket, since the 30 minutes per blade is significant 10% of my goal time and I estimate I can cut that easily down to half or maybe even less.

Making Kitchen Knives – Part 1 – In the Beginning…

… there was a bar of steel.

After a short break due to harvest I have started two knife making projects and I will share the progress on them as I go along.

The first one is about developing a viable process for making small-batches of kitchen knives.

The knife that I have given my mother for Christmas has proven itself to be an excellent cutter. It held an edge for half a year and still shaved hair when my mother requested honing the edge because it had a few blunt-ish spots. The handle does not show any sign of deterioration too. And it is used daily, by at least two people, on everything from fine chopping veggies to de-boning chicken. So I think that with some adjustments (mostly making it look prettier) it might be a saleable product.

I reckon (I will not bother you with the math and reasoning, some of it has solid rational basis, some of it I pulled out of my nether regions) that in order to be able to eventually barely survive whilst making knives, I would have to be able to make a passable kitchen knife in under five hours spending with the fun work, i.e. manual labor. The lower the better. Rest of the working day would in such a case be eaten by the unfunny part of the job, the actual business of business.

But developing a viable production process is something I have a professional experience with and so I want to have a go at it, even though right now making knives is just a hobby. And I will be sharing with you all the failures as well as the improvements in trying to achieve my time goal.

The first step is straightening the steel. For this project I am using N690 steel 1,8x50x500 mm and all the steel bars had a slight bend to them that had to be corrected. Currently the only way for me to do this is to use a vice and three thick screws. Had the plates had a kink, I would place the middle screw straight on that kink and bend it with ever-increasing pressure until after taking the steel out of the vice it would be straight-ish. However these did not have a kink, they were nearly universally bent in a very slight regular arc.  To straighten that, I first tried to bend the bars slightly at multiple points. It worked, but it was time-consuming and unreliable. Later I have tried to close the vice only slightly on the steel bar and then pulling it through the screws – essentially using it as an improvised roll bender. That worked much faster and reasonably well.

Even soo, all in all it took me less than 1 hour to straighten 12 knives worth of steel. That is less than 5 minutes per knife. I think that building a small roll bender specifically for straightening these thin long bars should not be difficult and it could potentially shave off quite a reasonable chunk off of that too. But right now, I am putting this into the “high hanging fruit” basket, since despite the clearly impromptu setting it takes only about 2% of my time goal. That means, I will ignore this step in the process for now and not bother about improving it.

For the first knife made let’s write down 5 minutes for this step and move on to the next.

Youtube Video: Pictish Crossbow – discussion and shooting

I would love to someday to build a crossbow. It definitively is on my ever growing to-do list.

Not that I feel particular inclination to be armed, but the simple yet not easy to make mechanism of a crossbow (or even a bow) intrigues me.

Tod Todeschini not only makes crossbows, he also likes to share his extensive knowledge about them. Here he uses that knowledge to speculate a bit about how pictish crossbows could look like.

I Was NOT Photographing Spiders!

During my photo walk previous week I tried to take “flash at dusk technique” of a dried up stalk of Heracleum sp. A bit before than, when the sun was still shining strong despite being low over the horizon, I tried to take a picture of a late blossom of Ranunculus sp.

However, as it transpired, I must put the pictures bellow the fold.

[Read more…]

Why Did You not Try to Stay in USA?

As readers of Affinity know, I was growing up until 13 years of age in a totalitarian state with little real autonomy, an effective satellite of USSR. I also grew up in a poor family so it was a bit of an uphill financial struggle for me to get a university education.

Towards the end of my education I had to decide how to actually start my independence and one of the options that presented themselves in 2000 was to go to USA with a “Work And Travel” program and J1 visa. I might write about my American adventure maybe some more later, today I wish to only briefly discuss the question in the title, which in various forms was posited to me in later years from many people here, old as well as young.

Even before venturing to USA I was of the opinion that it is a proto-fascist state and my opinion was further solidified by my experiences there.

So my answers at that time were these four points:

  1. Crappy healthcare. I have met ordinary people fearing that a simple case of flu might send them down the spiral of personal bankruptcy. I have seen outrageous prices for one course of antibiotics. I knew that USA had, in contrast to European countries, no universal healthcare, but seeing it first hand was a real eye opener. Fear of loosing even the crappy health insurance provided by the employer kept many people in essential slavery, when the were putting up with blatant abuse by their managers. For my friends I summed this argument up as “if I have grown up in USA, I would not live to become an adult, because my parents would not be able to pay for the medication I needed”.
  2. Crappy education. I have already mentioned that for me to get a university education was an uphill struggle. I was not bad student, but I am not so intelligent as to be able to study and work (not to mention that job availability was not that great – unemployment rate 8%), so I had only negligible income and I had to rely on my parents, which was hard – I had to live by with about 100,-$ a month to pay for my lodgings, food, books etc. For my friends I summed this argument up as “in USA I would not get a university degree, because even without tuition fees it was not cheap and with tuition fees it would be ruinous”.
  3. The mony that I made n USA was worthless there, it only had worth here because of the very favourable exchange rate. In US, the measly 5.50$/h were to barely live by – even though as a student I was tax exempt. So staying in USA would mean to lock myself into perpetual poverty. I find it incredible how many of my peers with university education failed to grasp this reality, that money’s worth is contextual and 1.000,-$ monthly income in USA is shit, whilst being absolutely amazing and nearly unattainable here.  I tried to sum it up as “for the money I was making there, I could not even rent a flat. And I would be forced to do work well bellow my qualification even for that. Here, I could use it to at least repair my house.”
  4. Absolutely inane laws and judiciary process. I have always thought that outcome of a judicial case should not be decided by a bunch of barely literate amateurs and that precedent law should not still be employed in any civilised country. And what I particularly did not admire was the “sue happy” culture in USA, where people try to win the lottery by suing each other for money. And the lack of properly functional system for “ex officio” advocates for people who cannot afford to pay. I summed it up as “any time you could get sued by some idiot over some trivial thing and if they could afford better lawyer than you, you are screwed”.

And mind you, this all was in 2000. The only progress that I see from behind the Atlantic was on health care, everything else got  much worse since then. And it seems that USA is managing to drag back the rest of the world as well – in last decade or so the main American exports are jingoism and creationism.

The USA was never democracy and never free. It only managed to convince its enslaved citizens that they are free. I am entirely content with my decision to not even try to live there permanently.

Bobbin Lace Masterpiece

I would like to share a both inspiring and gloomy story this time.

My grandmother was abandoned as a child by her family, who did not want to raise her – she has lost her leg and staunchly religious catholic matriarch of the family refused to take care of a “cripple”. So they gave her to a cloister to be raised by nuns. She learned there bobbin lace making style specific to that region of Domažlice.

©Charly, all rights reserved. Click for full size.

This piece is a tablecloth circa 60×80 cm and was started by my grandmother in that regional style. But she managed to only make some of the edges and corners before she died. My mother has kept those pieces and she intended to finish it at some time, but she could not get the right thread. After decades of searching both in real life and on the internet she found a vendor still selling what appeared to be the correct thread and she bought it.

Unfortunately, the new thread pieces did have slightly different color than the antique 50 years old ones (to be expected), so she could not simply continue her mother’s work. Therefore she started from scratch, only using grandmothers template for corners and edges.

For that I had to scan the template first.

©Charly, all rights reserved. Click for full size.

And then make it black-white, so my mother can take it and draw a new one with the time-tested technique of taping it on glass under a new sheet of paper and tracing the lines per hand.

©Charly, all rights reserved. Click for full size.

When the edges and corners were finished, she had to design the center part. She was not satisfied with her attempts and she requested my creative input. I proposed that chain of ovals with lobed edges around three stars, and she went with that idea and expanded it. They have a slightly different style, but I think it all works together.

So you see in effect a piece of art that took three-generations to complete, if you count my minuscule input. In the end, my mother has spent over 100 work hours making it, and used up over 1 km of thread. It is absolutely invaluable – and she gave it to me for my birthday this summer. I do not wish to use it as a tablecloth, so I framed it as a picture and I am in search of a piece of wall big enough to hang it on.

Sadly with me the bobbin-lace tradition in our family will die. I tried to learn it as a child and I was not bad at it, but I have way too many interests as it is so I forgot it again – and since probability of me ever having family converges to zero every year, I would not pass it on anyway.

But in the meantime, you can enjoy the pictures.

Anatomy Atlas Part 25 – Lymphatic System

You have no doubt noticed that some of the later pictures were a bit sloppy in their execution. Keep in mind that they were primarily a learning aide for me and they were not meant to be shared publicly. And whilst I did not post them in the exact order they were made, because they are not physically numbered and I of course do not remember it anymore, they were nevertheless posted in an approximate order. And I do remember that this one I have drawn as the last – and it is also the last one to be posted. This is the finale of the series.

©Charly, all rights reserved. Click for full size.

After this picture I did not need to work on these sheets anymore, because I have passed the anatomy exam and I had to invest my resources into other things.

I knew that I have only 25 sheets to post and I reckoned that posting one a week will be about the right tempo to keep the blog squeak along  with some regular and predictable content whilst giving Caine some much-needed respite. And I thought that at the time I will post my last sheet and bow out, she will be convalescing and getting back into her tempo.

Sadly, as it so often happens, the universe does not care about our presumptions and plans. Fuck cancer.

Behind the Iron Curtain part 19 – Pionýr

These are my recollections of a life behind the iron curtain. I do not aim to give perfect and objective evaluation of anything, but to share my personal experiences and memories. It will explain why I just cannot get misty eyed over some ideas on the political left and why I loathe many ideas on the right.

In my opinion, totalitarian regimes are very good at recognizing one crucial fact of life – it is important to reach children as soon as possible and indoctrinate them into your ideology, because later on it might not work. Throughout history of totalitarian regimes therefore are many examples of youth’s organizations whose main purpose was political.

The communist regime in former Soviet bloc was no different and the youth organization in our country was named “Pionýr” a derivative of the word pioneer, attempting to imply boldness and strength to freely explore hitherto unexplored. Where “freely” means “in the direction the party allows and if the conclusions confirm with party line”.

It started at an early age, about seven years, with a membership in “Jiskra” (spark), an organisation that was essentially preparing children for future membership in pionýr. After that, at the eight-nine years of age, the child could enter the Pionýr organization and become a full member.

Membership was confirmed by a public pledge first as Jiskra, then as Pionýr. I do not remember my Pionýr pledge, but I do remember some feelings about being overwhelmed by the Jiskra one, to the point that I still remember the first sentence of the pledge – but I had to look up the rest. I had my heart in my throat as I was standing in an auditorium in front of most of the town and piping up the pledge loud enough to be heard. I also remember that I actually believed and meant what I was saying.

Here are the translations (not trying to convey the cadence and rhyming of the originals):
Jiskra – “Slibuji dnes přede všemi, jako jiskra jasná, chci žít pro svou krásnou zemi, aby byla šťastná” – Like a bright spark I promise in front of all, that I want to live for my beautiful country so it can be happy.

Pionýr: “Slibuji před svými druhy, že budu pracovat, učit se a žít podle pionýrských zákonů, abych byl dobrým občanem své milované vlasti, Československé socialistické republiky, a svým jednáním chránit čest pionýrské organizace Socialistického svazu mládeže.” – I promise in front of my comrades, that I will work, learn and live by pionýr law, in order to become good citizen of my beloved country, Czechoslovak Socialist Republic, and with my behaviour I promise to guard the honor of the Pionýr organization of Socialist Youth Association.

Membership in Pionýr was not compulsory. But it was not compulsory in the sense “it is voluntary, but you must”. In my class, there were a few children who were not members, and our teacher – a fanatical communist to this day – did give them some grief for that. Remember what I said about education? Not being a member of Pionýr was a huge hindrance to getting meaningful highschool education, and made it nigh impossible to get into university later on. So most children entered the organization even when privately they and their parents disagreed with the regime.

I do not remember much about what we were doing in the name of the organization as such, apart from a few summer camps to which I went, and a few marches on memorable occasions (like of May). Maybe I will remember something more later.

I still have my red scarf in the cupboard, despite not agreeing with communist philosophy. I do not know why.